     -----------------------------------------------------------
                             README for
               Microsoft Windows Internet Explorer 5.5 
                        and Internet Tools Beta
                              March 2000
     -----------------------------------------------------------

               (c) Copyright Microsoft Corporation, 2000


This document provides complementary or late-breaking information 
to supplement the Microsoft(R) Windows(R) Internet Explorer and 
Internet Tools documentation. You can also see the Microsoft Web 
site for the latest information.

If you're looking for information about a specific program or 
component, try searching for it in the Microsoft Knowledge Base 
at http://support.microsoft.com. System requirements are listed 
in IE.txt which can be found in the Internet Explorer directory 
of your local computer's Program Files.


------------------------
HOW TO USE THIS DOCUMENT
------------------------

To view Iereadme.txt on screen in Notepad, maximize the Notepad 
window.

To print Iereadme.txt, open it in Notepad or another word 
processor, and then use the Print command on the File menu.


========
CONTENTS
========

SYSTEM REQUIREMENTS
  Disk-Space Requirements for Internet Explorer 5.5 Installation
  Installing Windows NT 4.0 Service Pack 4
SETUP
  Installing Internet Explorer 5.5 and Internet Tools Beta 
  Running Internet Explorer 5.5 on Microsoft Windows NT 4.0
  Installing Windows NT 4.0 Service Packs 
    Over Internet Explorer 5.5
  Installing over Windows 2000 Releases
  Uninstall Internet Explorer 5.5 Before Upgrading 
    to Windows 2000
  High Encryption Support for Internet Explorer 5.5 
  Running Internet Explorer 5.5 on a Dual-Boot Operating System
  Installing or Upgrading the Windows Desktop Update
  Installing over Localized Windows 98 Arabic and Hebrew Releases
  Installing Outlook Express 5 on Windows Terminal Server
  Installing Internet Explorer 5.5 with Norton Protected Recycle 
      Bin Enabled
  Installing on Windows 98 with Novell IPX/IP client
  Uninstalling Internet Explorer 5.5 and Internet Tools Beta
  Uninstall for Internet Explorer 4.x Unavailable
  Uninstalling Internet Explorer 5.5 Returns You 
    to an Earlier Version
ADDITIONAL ISSUES
  FTP User Interface and Functionality
  Font Display Issues
  Non-English Characters in URLs and Queries
  Internet Explorer 4.x Compatibility Mode
  Uninstalling Outlook Express 5 
  Radio Toolbar
  Changing the Language of Menus and Dialog Boxes
  AutoComplete Options
  Microsoft Chat 2.5
  Microsoft Wallet
  Enhanced Encryption Strength
DEVELOPER'S NOTES
  Frames Re-Architecture
  New Language Features in JScript and VBScript
  Character Encoding Issues 
  Document.expando=false Affects Entire 
    Internet Explorer Session
  The Microsoft Office Developer Workflow Toolbar
  Printing Controls
APPLICATION COMPATIBILITY
  Visual Studio 6.0
  DirecPC 2.0
  BackOffice Small Business Server
  Logitech Internet Keyboard
  Internet Explorer ActiveX Tree and Pop-up Menu Controls
  Task Scheduler in Windows NT 4.0
THE INDEPENDENT JPEG GROUP'S JPEG SOFTWARE README FOR RELEASE 6b



===================
SYSTEM REQUIREMENTS
===================

To run Internet Explorer 5.5 and Internet Tools Beta, your 
computer must meet the following minimum requirements:

- A 486 with a 66 MHz (megahertz) processor (Pentium processor 
	recommended)

- For Microsoft Windows 95 or Windows 98:
  16 MB (megabytes) of RAM (random access memory) minimum

  For Microsoft Windows NT(R) 4.0:
  32 MB of RAM minimum
  You must be running Service Pack 3 (or higher)

- For Microsoft Windows(R) 2000:
  64 MB of RAM minimum

- Minimal installation (browser only):
  	Required to install:    45 MB
  	Required to run:        27 MB after restart
  Typical installation:
  	Required to install:    70 MB
  	Required to run:        55 MB after restart
  Full installation:
  	Required to install:   111 MB
  	Required to run:        80 MB after restart

- Mouse

- Modem or Internet connection

- CD-ROM drive (if installation is done from a CD-ROM)

- Some components may require additional system resources
  not outlined above.

Disk-Space Requirements for Internet Explorer 5.5 Installation
---------------------------------------------------------------
Internet Explorer 5.5 and Internet Tools Beta Setup installs the 
majority of its files on the drive where the Windows operating 
system is installed, regardless of the installation location you 
chose. To free up space on your hard disk in order to meet the 
Internet Explorer 5.5 disk-space installation requirements, 
you must free up space on the drive where the Windows operating 
system is installed.

Installing Windows NT 4.0 Service Pack 4
----------------------------------------
After you install Windows NT 4.0 Service Pack 4 (SP4), but before 
you install Internet Explorer 5.5 and Internet Tools Beta, you 
may see a message recommending that you install one or both of 
the following Service Packs to resolve known Year 2000 issues:

- Internet Explorer 4.01 Service Pack 1
- Microsoft Data Access Components 2.0 Service Pack 1

You can ignore this message because Internet Explorer 5.5 
resolves the Year 2000 issues addressed in these Service Packs.


=====
SETUP
=====

Installing Internet Explorer 5.5 and Internet Tools Beta
--------------------------------------------------------
Whether you choose to install over the network or download the 
installation files to your hard disk, some or all of the Setup 
files are copied to your hard disk. This allows you to reinstall 
more quickly if necessary. If you want to reclaim the disk space, 
you can remove the Setup directory as follows:

1. In Windows Control Panel, open Add/Remove Programs, and then 
   click Internet Explorer 5.5 and Internet Tools Beta. 
2. Click Add/Remove, make sure the check box for Restore The 
   Previous Windows Configuration is selected, and then click 
   Advanced.
3. Click the option named Remove Folder Containing Windows Update 
   Setup Files, and then click OK. 
4. When asked whether you want to continue, click Yes.
5. Click OK in the next dialog boxes.

You cannot install Internet Explorer 5.5 and Internet Tools Beta 
to or run it from a network drive. However, you can download it 
to a network drive. To do this, you must map the network drive 
to a drive letter on your computer; you cannot download Internet 
Explorer 5.5 to a UNC path.

Running Internet Explorer 5.5 on Microsoft Windows NT 4.0
---------------------------------------------------------
NOTE: You must have administrative privileges to install and 
      uninstall this program on Windows NT. This includes 
      having administrative privileges the first time you 
      start your computer after installing or uninstalling.

You must restart your computer after installing Internet Explorer 
5.5 and Internet Tools Beta. This is also true for some add-on 
components.

For corporate deployment on computers running Windows NT 4.0, 
make sure you have the following free registry space:

- If you are upgrading from Internet Explorer 2.0 or 
  Internet Explorer 3.x: at least 4 MB
- If you are upgrading from Internet Explorer 4.x:
  at least 2.5 MB 

If you're running Internet Explorer 5.5 on Windows NT 4.0, 
you must set user permissions to Full Control for the 
Temporary Internet Files folder (cache). The user must 
have write permission so that files can be stored in the 
Temporary Internet Files folder.

If you must reinstall Windows NT 4.0 Service Pack 3 (SP3) after 
you install Internet Explorer 5.5 and Internet Tools Beta, you 
must specify when prompted that you do not want it to overwrite 
any files that are newer. After SP3 is reinstalled, carry out 
the following steps to update the registry:

1. Click the Start button, and then click Run.
2. Type the following: regsvr32 rsabase.dll

Installing Windows NT 4.0 Service Packs 
Over Internet Explorer 5.5 
---------------------------------------
If you reinstall a Windows NT 4.0 Service Pack after Internet 
Explorer 5.5 and Internet Tools Beta is installed on your 
computer, some components will need to be re-registered. To 
do this, carry out the following steps:

1. In Windows Control Panel, open Add/Remove Programs.
2. On the Install/Uninstall tab, click Microsoft Internet 
   Explorer 5.5 and Internet Tools Beta.
3. Click Add/Remove.
4. Click Repair Internet Explorer, and then click OK.
5. After the repair operation is complete, restart your computer.

Installing over Windows 2000 Releases
-------------------------------------
Typical and Full installs are not currently available for Windows 
2000. Internet Explorer 5.5 will install a minimal set of files 
into your system. This includes Internet Explorer 5.5 Web browser 
and scripting support.

Uninstall Internet Explorer 5.5 
Before Upgrading to Windows 2000
--------------------------------
Windows 2000 contains Internet Explorer 5.01. When upgrading from
Windows 9x or Windows NT to Windows 2000, we recommend that you 
uninstall Internet Explorer 5.5 before the upgrade.

During the upgrade, you may notice the following message "This 
program may not run correctly because of new features in Internet 
Explorer 4.0. You may need to obtain an updated version of this 
program...". This message is misleading. For a more accurate 
description of the problem, click the Details button.

High Encryption Support For Internet Explorer 5.5 
-------------------------------------------------
Internet Explorer 5.5 now includes 128-bit security, which 
provides the highest level of encryption when you visit 
secure Web sites. This may not be available in certain 
countries/regions due to local import restrictions.

Running Internet Explorer 5.5 
on a Dual-Boot Operating System
-------------------------------
If you are running Internet Explorer 5.5 on a computer that is 
set up to dual boot between two operating systems on the same 
partition (for example, Windows 95 and Windows NT 4.0), and you 
have configured the computer to share a single Program Files 
folder, you may have problems with add-on components. 

Also, when you uninstall an add-on component from either copy 
of Internet Explorer 5.5, it will be removed from both of them 
without updating the other operating system's installed 
components information. 

These problems are because the add-on files are all stored in 
the shared Program Files folder, but information about installed 
add-on components is stored elsewhere.

Installing or Upgrading the Windows Desktop Update
--------------------------------------------------
To install or upgrade the Windows Desktop Update, you must 
install Internet Explorer 4.01 SP2 before you install Internet 
Explorer 5.5 and Internet Tools. 

If you have already installed Internet Explorer 5.5 and would 
like to install the Windows Desktop Update, carry out the 
following steps:

1. Uninstall Internet Explorer 5.5 by using the procedure 
   outlined later in this document.
2. If Internet Explorer 4.01 SP2 is not already installed on your 
   computer, install it.
3. Install the Windows Desktop Update by using Add/Remove 
   Programs in Windows Control Panel.
4. Reinstall Internet Explorer 5.5 and Internet Tools Beta.

Installing over Localized Windows 98 
Arabic and Hebrew Releases
------------------------------------
Windows 98 Arabic and Hebrew versions require the corresponding 
localized version of Internet Explorer 5.5. It is not possible 
to install the English version of Internet Explorer over the 
localized version of Windows 98. 

This restriction does not apply to localized versions of 
Windows 95 or Windows NT 4.0. However, you cannot install 
localized Arabic or Hebrew Internet Explorer 5.5 on top of 
localized Windows 95 (only English is supported). 

Installing Outlook Express 5 on Windows Terminal Server
-------------------------------------------------------
Before installing Outlook Express 5 on Windows Terminal Server, 
the administrator needs to set a compatibility flag in the 
registry for the Outlook Express 5 Setup program to work 
correctly. To do this, carry out the following steps:

1. Create this registry key:

   HKEY_LOCAL_MACHINE\Microsoft\Windows NT\CurrentVersion\
   Terminal Server\Compatibility\Applications\setup50

2. Set the following value under the new setup50 key (this value 
   should be of type REG_DWORD): 

   Flags = 0x108

Installing Internet Explorer 5.5 with 
Norton Protected Recycle Bin Enabled
-------------------------------------
It is recommended that you disable the Norton Protected Recycle 
Bin while you install Internet Explorer 5.5 and Internet Tools 
Beta, and that you empty the Norton Protected Recycle Bin before 
you run Setup. Before you empty the Norton Protected Recycle Bin, 
be sure you review its contents in case it contains any items you 
want to recover safely. You can re-enable this feature after 
Setup is complete.

This is recommended because Norton Protected Recycle Bin will 
intercept the removal of temporary files that Setup is trying to 
delete, and you could run out of free space on your hard disk if 
your remaining free space is limited. This would cause Internet 
Explorer Setup to appear locked. For instructions on disabling 
and re-enabling the Norton Protected Recycle Bin, see the Norton 
Utilities documentation.

Installing on Windows 98 with Novell IPX/IP Client
--------------------------------------------------
If you are using Novell IPX/IP client with Windows 98, you may 
experience problems if you install Internet Explorer 5.5 and 
Internet Tools from the Internet. If Setup appears to become 
unresponsive, restart your computer. Setup will continue and 
finish normally. To work around this problem, try one of the 
following options:

- In Setup, select the Download Only option, and then run and 
  install Internet Explorer 5.5 normally.

- Install Internet Explorer 5.5 from a CD-ROM.

Uninstalling Internet Explorer 5.5 and Internet Tools Beta
----------------------------------------------------------
You can uninstall Internet Explorer 5.5 and Internet Tools Beta 
by carrying out the following steps:

1. In Windows Control Panel, open Add/Remove Programs.
2. Click Microsoft Internet Explorer 5.5 and Internet Tools Beta, 
   and then click Add/Remove.
3. Click Restore The Previous Windows Configuration, and then 
   click OK.
4. Follow the instructions on your screen.

Uninstall for Internet Explorer 4.x Unavailable
-----------------------------------------------
If you uninstall Internet Explorer 5.5, you will not be able 
to remove the browser that was installed prior to Internet 
Explorer 5.5.

Uninstalling Internet Explorer 5.5 
Returns You to an Earlier Version
----------------------------------
When you install Internet Explorer 5.5, Setup examines your 
system for the presence of uninstall data that had had been 
created by a previous installation. If it cannot find this data, 
it will create new uninstall data for later use.

If you previously upgraded from Internet Explorer 4.x to 5.0 
(or 5.01), you will have uninstall data that allows you to roll 
back to Internet Explorer 4.x. Unless you explicitly removed the 
uninstall data by using Add/Remove Programs in Windows Control 
Panel before upgrading to Internet Explorer 5.5, this data will 
be preserved. When you uninstall Internet Explorer 5.5, it will 
use the existing uninstall data and roll back to Internet 
Explorer 4.x.

The following chart lists the various upgrade scenarios and the 
Internet Explorer 5.5 uninstallation behavior that can occur in 
each case:

+--------------------------------------------------------------------------+
| Previous Version      | Uninstall data | Uninstall Results               | 
+--------------------------------------------------------------------------+
| Internet Explorer 3.x | n/a            | Internet Explorer 3.x           | 
+--------------------------------------------------------------------------+
| Internet Explorer 4.x | n/a            | Internet Explorer 4.x           | 
+--------------------------------------------------------------------------+
| Internet Explorer 5   | exists         | Pre-Internet Explorer 5 version | 
+--------------------------------------------------------------------------+
| Internet Explorer 5   | doesn't exist  | Internet Explorer 5             | 
+--------------------------------------------------------------------------+
| Windows 98            |                | Windows 98                      |
|(Internet Explorer 4)  | n/a            | (Internet Explorer 4)           | 
+--------------------------------------------------------------------------+
| Windows 98 SE         |                | Windows 98 SE                   |
|(Internet Explorer 5)  | n/a            | (Internet Explorer 5)           | 
+--------------------------------------------------------------------------+


=================
ADDITIONAL ISSUES
=================

FTP User Interface and Functionality
------------------------------------
If you discover an issue in the FTP user interface that blocks 
FTP functionality, you can disable this feature on the Advanced 
tab in the Internet Options dialog box.
 
The following functionality is not supported:
 
- Internet connection via CERN or Web proxy servers.
- Connecting to VAX or VMS FTP servers.
- Using the browser from within a separate application or service.
- Copying from server to server.
- Drag and drop or copy and paste functionality from an FTP 
  server is supported only on Windows 2000, Windows ME, and later.

Font Display Issues
-------------------
If you run a non-Asian language version of Windows NT 4.0 and 
you have installed many large fonts, the system's ability to use 
those fonts may be exceeded. If Asian language Web pages are not 
displayed correctly, install Windows NT 4.0 Service Pack 5.

Non-English Characters in URLs and Queries
------------------------------------------
Internet Explorer 5.5 uses a new standard to transmit non-English 
addresses (URLs) to the server. URLs are now encoded in a 
character encoding standard named UTF-8. If the server is running 
Microsoft Internet Information Server 4 or later, the URLs will 
work as expected. Many servers cannot process URLs encoded in 
UTF-8. To use non-English characters in URLs with these servers, 
carry out the following steps:
 
1. On the Tools menu in the browser, click Internet Options.
2. Click the Advanced tab.
3. Under Browsing, clear the Always Send URLs As UTF-8 check box.
 
The query part of URLs is transmitted in a form fully compatible 
with Internet Explorer 4.

Internet Explorer 4.x Compatibility Mode
----------------------------------------
The Internet Explorer 4.x compatibility option is useful to Web 
developers who want to view and test their Web sites on different 
versions of Internet Explorer using the same computer. You may 
not be able to change all settings for the browser while in this 
mode. When using the compatibility option, you should change 
Internet options through Windows Control Panel, not through the 
Internet Options command on the browser's Tools menu.

Uninstalling Outlook Express 5 
------------------------------ 
If you uninstall Outlook Express 5 and you were previously 
running Internet Mail and News, you will be able to see only 
the messages you received using Internet Mail and News. To view 
Outlook Express 5 messages, you must reinstall Outlook Express 5. 
 
If you uninstall Outlook Express 5 and you were previously 
running Outlook Express 4, you can view your Outlook Express 5 
messages in version 4 by carrying out the following steps:

1. On the File menu in Outlook Express, click Import, and then 
   click Messages.
2. In the list of programs, click Microsoft Outlook Express 5.
3. Follow the instructions on your screen.

Radio Toolbar
-------------
Internet Explorer 5.5 includes a Radio toolbar that allows 
streaming radio playback. By default, the toolbar is not 
displayed when the browser is started. To display the toolbar 
whenever the browser is started, carry out the following steps:

1. On the Tools menu in the browser, click Internet Options.
2. Click the Advanced tab.
3. Under Multimedia, select the check box labeled Always Show 
   Internet Explorer (5.0 or Later) Radio Bar.

Changing the Language of Menus and Dialog Boxes
-----------------------------------------------
Changing the language used in menus and dialog boxes may not work 
with all display adapters. If you see blank menus or dialog boxes 
after changing the language, try either of the following options:

- Change the resolution of your display adapter.
- Upgrade the driver for your display adapter to a newer 
  version. For information about updated drivers, contact 
  the manufacturer of your display adapter.

AutoComplete Options
--------------------
If you do not want AutoComplete to suggest matches for certain 
sensitive items you have previously entered, you have several 
options:

- To delete a specific AutoComplete entry, highlight it in the 
  AutoComplete drop-down list and then press DELETE.
- To delete a user name/password combination on a login page, 
  delete the user name; the password will be deleted with it.
- To clear all form or password information, do the following:

  1. On the Tools menu in the browser, click Internet Options.
  2. Click the Content tab. 
  3. Click AutoComplete, and then click Clear Forms or Clear 
     Passwords.

Microsoft Chat 2.5
------------------
You can no longer install Microsoft Chat 2.5 when installing 
Internet Explorer 5.5 and Internet Tools Beta. If you previously 
installed Microsoft Chat 2.5 and then upgraded to Internet 
Explorer 5.5, you will be able to continue to use your existing 
Microsoft Chat 2.5 client for a limited time on the Microsoft 
Chat servers. If you do not have a Chat client already installed 
and you would like to install one, or if you already have a 
version of Microsoft Chat installed, consider installing the 
new MSN Chat from http://webchat.msn.com. 

Microsoft Wallet
----------------
Microsoft Wallet is no longer available for installation in 
Internet Explorer 5.5. If you have previously installed 
Microsoft Wallet and then upgraded to Internet Explorer 5.5, 
you can continue to manage your Wallet information from Web 
sites that use the Wallet interface.

Enhanced Encryption Strength
----------------------------
Internet Explorer 5.5 now ships with standard encryption strength 
of 128 bits and supports the U.S. government standard for data 
encryption (DES). 128-bit Internet Explorer 5.5 is eligible 
for distribution to all users worldwide except in U.S. embargoed 
destinations. For more information, visit the following Web site:

     http://www.microsoft.com/exporting/


=================
DEVELOPER'S NOTES
=================

Frames Re-Architecture
----------------------
Microsoft is in the process of re-architecting the <frame> and 
<iframe> implementation for Internet Explorer. Many of the issues 
have been solved, but we have not reached full compatibility in 
this beta release. Please send feedback with any problems you 
discover so we can make sure we are compatible.

Every frame inside Internet Explorer used to be an instance of 
the Web Browser Control. We no longer use this implementation. 
Instead of hosting a Web Browser Control instance, which hosts 
another instance of Mshtml.dll, Mshtml.dll handles the rendering 
of frames itself.

New Language Features in JScript and VBScript
---------------------------------------------
Internet Explorer 5.5 ships with new versions of Microsoft 
JScript(R) and Visual Basic Scripting Edition (VBScript). The 
documentation for the new language features is not yet complete, 
but will be available at the time Internet Explorer 5.5 is 
released. You can read about the most important new features 
in JScript and VBScript at the following Web site:

http://msdn.microsoft.com/workshop/languages/clinic/scripting121399.asp

Note that the object model for VBScript Regular Expressions has 
been updated since this document was published. Each Match object 
has a 'SubMatches' collection, which has a 'Count' property and 
an 'Item' method for retrieving the submatches.

The updated Windows Script engines will also be posted for 
individual download from http://msdn.microsoft.com/scripting/ 
so they can be installed on computers that are not running 
Internet Explorer 5.5--for example, on an ASP web server.

Character Encoding Issues
------------------------- 
There are problems with the Internet Explorer 5.5 support for 
different character encodings within frames. For example, if 
you regularly read e-mail on Hotmail that is written with 
different character encodings, you may not be able to switch 
the encoding. To work around this issue, right-click the link, 
and then click Open In New Window in order to display the page 
with the correct encoding. This problem will be fixed in the 
final release of Internet Explorer 5.5.

Document.expando=false Affects 
Entire Internet Explorer Session
-------------------------------- 
There is a known issue in Beta 3 whereby turning off expandos 
(via document.expando=false) causes expandos to be turned off 
permanently for that instance of Internet Explorer. Even if you 
refresh or navigate to a new page, expandos will still be turned 
off. This will cause subsequent pages that rely on expandos to 
fail. To work around this problem, close Internet Explorer and 
start a new instance (to reset expandos to the default of On) 
OR to explicitly set document.expando=true via script code.

The Microsoft Office Developer Workflow Toolbar
-----------------------------------------------
In this release of Internet Explorer, the Microsoft Office 
Developer Workflow Toolbar control will not data bind properly 
on an Access data page. This control was affected by a fix in 
Internet Explorer 5.5, so an update of this control will be 
necessary. For the latest updates, visit the following Web 
page:

     http://microsoft.com/office/

Printing Controls
-----------------
The re-architecting of the print code in Internet Explorer 5.5 
has exposed print bugs in several third-party controls, causing 
some controls to print improperly and some not to print at all. 
We will strive for print compatibility when the final product 
is released; however, we cannot ensure that all third parties 
will have corrected these bugs.


=========================
APPLICATION COMPATIBILITY
=========================

Visual Studio 6.0
-----------------
There are some known issues when Microsoft Visual Studio(R) 6.0 
and Internet Explorer 5.5 are installed on the same computer. 
These issues are resolved with Microsoft Visual Studio 6.0 SP3. 
If you are running Visual Studio 6.0, it is recommended that you 
upgrade to SP3 at http://msdn.microsoft.com/vstudio/sp/vs6sp3/.

DirecPC 2.0
-----------
After you install Internet Explorer 5.5 and Internet Tools 
Beta on a computer running DirecPC 2.0, you may receive an 
error message when starting the DirecPC software. To correct 
this problem, contact Hughes Network Systems to obtain an 
updated version of the DirecPC software.

BackOffice Small Business Server
--------------------------------
If you use BackOffice(R) Small Business Server, you must upgrade 
to Small Business Server 4.5 before installing Internet Explorer 
5.5 and Internet Tools. Without the upgrade, the SBS management 
console flickers with each screen transition. Increasing the 
number of colors helps the problem but does not resolve it.

Logitech Internet Keyboard
--------------------------
Certain versions of the Key Commander software that ship with 
the Logitech Internet Keyboard are not compatible with Internet 
Explorer 5.5. For more information, contact Logitech Customer 
Support or see the Logitech Web site at http://www.logitech.com.

Internet Explorer ActiveX Tree and Pop-up Menu Controls
-------------------------------------------------------
When you install Internet Explorer 5.5 and Internet Tools Beta, 
the Setup program removes earlier versions of the ActiveX tree 
control and pop-up menu controls because of compatibility issues 
with this version of the browser. If you are running a program 
that relies on these controls, you may have to reinstall the 
controls to restore functionality.

Task Scheduler in Windows NT 4.0
--------------------------------
Windows NT 4.0 included an old version of the Schedule service, 
also known as At service (Atsvc.exe). Internet Explorer 5.5 
upgrades it to the new version of the Schedule service, named 
Task Scheduler (MSTask.exe) and converts At jobs to Scheduled 
Tasks.

With the old At service, all At jobs had to run in the same 
account as the service itself. The default account for the 
service was the Local System account, but it could be changed 
to another user account if desired. Some Windows NT 4.0 users 
changed the At service's account because they needed their jobs 
to run in a user account. 

With Task Scheduler, each scheduled task can be configured to 
run in a different account. The Task Scheduler service itself 
has to run in the Local System account.

For backward compatibility, Task Scheduler allows the user to 
set one account to use when running scheduled tasks that were 
created from At jobs. When Internet Explorer 5.5 is installed, 
this account is set to the Local System account. If you are 
running Windows NT 4.0 and you change the account that the At 
service ran in to something other than the Local System account, 
then after installing Internet Explorer 5.5 you need to manually 
re-enter the user name and password for that account. To do this, 
in the Scheduled Tasks folder, click the Advanced menu, and then 
click AT Service Account. 

This must be done manually because Internet Explorer 5.5 Setup 
cannot decrypt the password that was used by the At service.

For more information about At service compatibility, see online 
Help in Task Scheduler.


======================================
MICROSOFT CORPORATION EXPLANATORY NOTE
======================================

Because Microsoft has included the source code of the Independent 
JPEG Group's JPEG software in this product, Microsoft is 
obligated to also include the README file that accompanied such 
software, which README file contains information regarding a 
separate ansi2knr.c program. Microsoft has chosen not to 
distribute the additional ansi2knr.c program so the provisions 
in the README file below regarding the inclusion of such program 
are not pertinent to this product. 


          ==========================================
          THE INDEPENDENT JPEG GROUP'S JPEG SOFTWARE
             README for release 6b of 27-Mar-1998
          ==========================================

This distribution contains the sixth public release of the 
Independent JPEG Group's free JPEG software. You are welcome 
to redistribute this software and to use it for any purpose, 
subject to the conditions under LEGAL ISSUES, below.

Serious users of this software (particularly those incorporating 
it into larger programs) should contact IJG at the following 
address:

     jpeg-info@uunet.uu.net <mailto:jpeg-info@uunet.uu.net> 

to be added to our electronic mailing list. Mailing list members 
are notified of updates and have a chance to participate in 
technical discussions, etc.

This software is the work of Tom Lane, Philip Gladstone, Jim 
Boucher, Lee Crocker, Julian Minguillon, Luis Ortiz, George 
Phillips, Davide Rossi, Guido Vollbeding, Ge' Weijers, and 
other members of the Independent JPEG Group.

IJG is not affiliated with the official ISO JPEG standards 
committee.


=====================
DOCUMENTATION ROADMAP
=====================

This file contains the following sections:

OVERVIEW            General description of JPEG and the IJG 
                      software.
LEGAL ISSUES        Copyright, lack of warranty, terms of 
                      distribution.
REFERENCES          Where to learn more about JPEG.
ARCHIVE LOCATIONS   Where to find newer versions of this 
                      software.
RELATED SOFTWARE    Other stuff you should get.
FILE FORMAT WARS    Software *not* to get.
TO DO               Plans for future IJG releases.

Other documentation files in the distribution are:

User documentation:
  install.doc       How to configure and install the IJG software.
  usage.doc         Usage instructions for cjpeg, djpeg, jpegtran,
                    rdjpgcom, and wrjpgcom.
  *.1               UNIX-style man pages for programs 
                      (same info as usage.doc).
  wizard.doc        Advanced usage instructions for JPEG wizards 
                      only.
  change.log        Version-to-version change highlights.

Programmer and internal documentation:
  libjpeg.doc       How to use the JPEG library in your own 
                      programs.
  example.c         Sample code for calling the JPEG library.
  structure.doc     Overview of the JPEG library's internal 
                      structure.
  filelist.doc      Road map of IJG files.
  coderules.doc     Coding style rules--please read if you 
                      contribute code.

Please read at least the files install.doc and usage.doc. Useful 
information can also be found in the JPEG FAQ (Frequently Asked 
Questions) article. See ARCHIVE LOCATIONS below to find out 
where to obtain the FAQ article.

If you want to understand how the JPEG code works, we suggest 
reading one or more of the REFERENCES, then looking at the 
documentation files (in roughly the order listed) before diving 
into the code.


========
OVERVIEW
========

This package contains C software to implement JPEG image 
compression and decompression. JPEG (pronounced "jay-peg") is a 
standardized compression method for full-color and gray-scale 
images. JPEG is intended for compressing "real-world" scenes; 
line drawings, cartoons and other non-realistic images are not 
its strong suit. JPEG is lossy, meaning that the output image 
is not exactly identical to the input image. Hence you must not 
use JPEG if you have to have identical output bits. However, on 
typical photographic images, very good compression levels can be 
obtained with no visible change, and remarkably high compression 
levels are possible if you can tolerate a low-quality image. For 
more details, see the references, or just experiment with various 
compression settings.

This software implements JPEG baseline, extended-sequential, 
and progressive compression processes. Provision is made for 
supporting all variants of these processes, although some uncommon 
parameter settings aren't implemented yet. For legal reasons, we 
are not distributing code for the arithmetic-coding variants of 
JPEG; see LEGAL ISSUES. We have made no provision for supporting 
the hierarchical or lossless processes defined in the standard.

We provide a set of library routines for reading and writing JPEG 
image files, plus two sample applications "cjpeg" and "djpeg", 
which use the library to perform conversion between JPEG and some 
other popular image file formats. The library is intended to be 
reused in other applications.

In order to support file conversion and viewing software, we have 
included considerable functionality beyond the bare JPEG coding/
decoding capability; for example, the color quantization modules 
are not strictly part of JPEG decoding, but they are essential 
for output to colormapped file formats or colormapped displays. 
These extra functions can be compiled out of the library if not 
required for a particular application. We have also included 
"jpegtran", a utility for lossless transcoding between different 
JPEG processes, and "rdjpgcom" and "wrjpgcom", two simple 
applications for inserting and extracting textual comments in 
JFIF files.

The emphasis in designing this software has been on achieving 
portability and flexibility, while also making it fast enough 
to be useful. In particular, the software is not intended to be 
read as a tutorial on JPEG. (See the REFERENCES section for 
introductory material.) Rather, it is intended to be reliable, 
portable, industrial-strength code. We do not claim to have 
achieved that goal in every aspect of the software, but we 
strive for it.

We welcome the use of this software as a component of commercial 
products. No royalty is required, but we do ask for an 
acknowledgement in product documentation, as described under 
LEGAL ISSUES.


============
LEGAL ISSUES
============

In plain English:

1. We don't promise that this software works. (But if you find 
   any bugs, please let us know!)
2. You can use this software for whatever you want. You don't 
   have to pay us.
3. You may not pretend that you wrote this software. If you use 
   it in a program, you must acknowledge somewhere in your 
   documentation that you've used the IJG code.

In legalese:

The authors make NO WARRANTY or representation, either express 
or implied, with respect to this software, its quality, accuracy, 
merchantability, or fitness for a particular purpose. This 
software is provided "AS IS", and you, its user, assume the 
entire risk as to its quality and accuracy.

This software is copyright (C) 1991-1998, Thomas G. Lane.
All Rights Reserved except as specified below.

Permission is hereby granted to use, copy, modify, and distribute 
this software (or portions thereof) for any purpose, without fee, 
subject to these conditions:
(1) If any part of the source code for this software is 
distributed, then this README file must be included, with this 
copyright and no-warranty notice unaltered; and any additions, 
deletions, or changes to the original files must be clearly 
indicated in accompanying documentation.
(2) If only executable code is distributed, then the accompanying
documentation must state that "this software is based in part on 
the work of the Independent JPEG Group".
(3) Permission for use of this software is granted only if the 
user accepts full responsibility for any undesirable consequences; 
the authors accept NO LIABILITY for damages of any kind.

These conditions apply to any software derived from or based on 
the IJG code, not just to the unmodified library. If you use our 
work, you ought to acknowledge us.

Permission is NOT granted for the use of any IJG author's name 
or company name in advertising or publicity relating to this 
software or products derived from it. This software may be 
referred to only as "the Independent JPEG Group's software".

We specifically permit and encourage the use of this software as 
the basis of commercial products, provided that all warranty or 
liability claims are assumed by the product vendor.

ansi2knr.c is included in this distribution by permission of 
L. Peter Deutsch, sole proprietor of its copyright holder, 
Aladdin Enterprises of Menlo Park, CA. ansi2knr.c is NOT covered 
by the above copyright and conditions, but instead by the usual 
distribution terms of the Free Software Foundation; principally, 
that you must include source code if you redistribute it. (See 
the file ansi2knr.c for full details.) However, since ansi2knr.c 
is not needed as part of any program generated from the IJG code, 
this does not limit you more than the foregoing paragraphs do.

The UNIX configuration script "configure" was produced with GNU 
Autoconf. It is copyright by the Free Software Foundation but is 
freely distributable. The same holds for its supporting scripts 
(config.guess, config.sub, ltconfig, ltmain.sh). Another support 
script, install-sh, is copyright by M.I.T. but is also freely 
distributable.

It appears that the arithmetic coding option of the JPEG spec is 
covered by patents owned by IBM, AT&T, and Mitsubishi. Hence 
arithmetic coding cannot legally be used without obtaining one 
or more licenses. For this reason, support for arithmetic coding 
has been removed from the free JPEG software. (Since arithmetic 
coding provides only a marginal gain over the unpatented Huffman 
mode, it is unlikely that very many implementations will support 
it.) So far as we are aware, there are no patent restrictions on 
the remaining code.

The IJG distribution formerly included code to read and write 
GIF files. To avoid entanglement with the Unisys LZW patent, GIF 
reading support has been removed altogether, and the GIF writer 
has been simplified to produce "uncompressed GIFs". This 
technique does not use the LZW algorithm; the resulting GIF 
files are larger than usual, but are readable by all standard 
GIF decoders.

We are required to state that
    "The Graphics Interchange Format(c) is the Copyright property 
    of CompuServe Incorporated. GIF(sm) is a Service Mark property 
    of CompuServe Incorporated."


==========
REFERENCES
==========
We highly recommend reading one or more of these references 
before trying to understand the innards of the JPEG software.

The best short technical introduction to the JPEG compression 
algorithm is:

      Wallace, Gregory K. "The JPEG Still Picture Compression 
      Standard", Communications of the ACM, April 1991 
      (vol. 34 no. 4), pp. 30-44.

(Adjacent articles in that issue discuss MPEG motion picture 
compression, applications of JPEG, and related topics.) If you 
don't have the CACM issue handy, a PostScript file containing a 
revised version of Wallace's article is available at
<ftp://ftp.uu.net/graphics/jpeg/wallace.ps.gz>. The file 
(actually a preprint for an article that appeared in IEEE Trans. 
Consumer Electronics) omits the sample images that appeared in 
CACM, but it includes corrections and some added material. 
Note: the Wallace article is copyright ACM and IEEE, and it may 
not be used for commercial purposes.

A somewhat less technical, more leisurely introduction to JPEG 
can be found in "The Data Compression Book" by Mark Nelson and 
Jean-loup Gailly, published by M&T Books (New York), 2nd ed. 
1996, ISBN 1-55851-434-1. This book provides good explanations 
and example C code for a multitude of compression methods 
including JPEG. It is an excellent source if you are comfortable 
reading C code but don't know much about data compression in 
general. The book's JPEG sample code is far from industrial-
strength, but when you are ready to look at a full 
implementation, you've got one here...

The best full description of JPEG is the textbook "JPEG Still 
Image Data Compression Standard" by William B. Pennebaker and 
Joan L. Mitchell, published by Van Nostrand Reinhold, 1993, 
ISBN 0-442-01272-1. Price US$59.95, 638 pp. The book includes 
the complete text of the ISO JPEG standards (DIS 10918-1 and 
draft DIS 10918-2). This is by far the most complete exposition 
of JPEG in existence, and we highly recommend it.

The JPEG standard itself is not available electronically; you 
must order a paper copy through ISO or ITU. (Unless you feel a 
need to own a certified official copy, we recommend buying the 
Pennebaker and Mitchell book instead; it's much cheaper and 
includes a great deal of useful explanatory material.) In the 
USA, copies of the standard may be ordered from ANSI Sales at 
(212) 642-4900, or from Global Engineering Documents at 
(800) 854-7179. (ANSI doesn't take credit card orders, but 
Global does.) It's not cheap: as of 1992, ANSI was charging 
$95 for Part 1 and $47 for Part 2, plus 7% shipping/handling. 
The standard is divided into two parts, Part 1 being the actual 
specification, while Part 2 covers compliance testing methods. 
Part 1 is titled "Digital Compression and Coding of Continuous-
tone Still Images, Part 1: Requirements and guidelines" and has 
document numbers ISO/IEC IS 10918-1, ITU-T T.81. Part 2 is 
titled "Digital Compression and Coding of Continuous-tone Still 
Images, Part 2: Compliance testing" and has document numbers 
ISO/IEC IS 10918-2, ITU-T T.83.

Some extensions to the original JPEG standard are defined in 
JPEG Part 3, a newer ISO standard numbered ISO/IEC IS 10918-3 
and ITU-T T.84. IJG currently does not support any Part 3 
extensions.

The JPEG standard does not specify all details of an 
interchangeable file format. For the omitted details we follow 
the "JFIF" conventions, revision 1.02. A copy of the JFIF spec 
is available from:

	Literature Department
	C-Cube Microsystems, Inc.
	1778 McCarthy Blvd.
	Milpitas, CA 95035
	phone (408) 944-6300,  fax (408) 944-6314

A PostScript version of this document is available by FTP at
<ftp://ftp.uu.net/graphics/jpeg/jfif.ps.gz>. There is also a 
plain text version at 
<ftp://ftp.uu.net/graphics/jpeg/jfif.txt.gz>, but it is missing 
the figures.

The TIFF 6.0 file format specification can be obtained by FTP 
from <ftp://ftp.sgi.com/graphics/tiff/TIFF6.ps.gz>. The JPEG 
incorporation scheme found in the TIFF 6.0 spec of 3-June-92 
has a number of serious problems. IJG does not recommend use 
of the TIFF 6.0 design (TIFF Compression tag 6). Instead, we 
recommend the JPEG design proposed by TIFF Technical Note #2 
(Compression tag 7). Copies of this Note can be obtained from 
ftp.sgi.com <ftp://ftp.sgi.com> or from 
<ftp://ftp.uu.net/graphics/jpeg/>. It is expected that the next 
revision of the TIFF spec will replace the 6.0 JPEG design with 
the Note's design. Although IJG's own code does not support 
TIFF/JPEG, the free libtiff library uses our library to 
implement TIFF/JPEG per the Note. libtiff is available from 
<ftp://ftp.sgi.com/graphics/tiff/>.


=================
ARCHIVE LOCATIONS
=================

The "official" archive site for this software is ftp.uu.net 
<ftp://ftp.uu.net> (Internet address 192.48.96.9). The most 
recent released version can always be found there in directory 
graphics/jpeg. This particular version will be archived as  <ftp://ftp.uu.net/graphics/jpeg/jpegsrc.v6b.tar.gz>. If you don't 
have direct Internet access, UUNET's archives are also available 
via UUCP; contact help@uunet.uu.net <mailto:help@uunet.uu.net> 
for information on retrieving files that way.

Numerous Internet sites maintain copies of the UUNET files. 
However, only ftp.uu.net <ftp://ftp.uu.net> is guaranteed to 
have the latest official version.

You can also obtain this software in DOS-compatible "zip" 
archive format from the SimTel archives 
(<ftp://ftp.simtel.net/pub/simtelnet/msdos/graphics/>), or on 
CompuServe in the Graphics Support forum (GO CIS:GRAPHSUP), 
library 12 "JPEG Tools". Again, these versions may sometimes 
lag behind the ftp.uu.net <ftp://ftp.uu.net> release.

The JPEG FAQ (Frequently Asked Questions) article is a useful 
source of general information about JPEG. It is updated 
constantly and therefore is not included in this distribution. 
The FAQ is posted every two weeks to Usenet newsgroups 
comp.graphics.misc, news.answers, and other groups. It is 
available on the World Wide Web at 
<http://www.faqs.org/faqs/jpeg-faq/> and other news.answers 
archive sites, including the official news.answers archive at 
rtfm.mit.edu: <ftp://rtfm.mit.edu/pub/usenet/news.answers/jpeg-faq/>.
If you don't have Web or FTP access, send e-mail to 
mail-server@rtfm.mit.edu <mailto:mail-server@rtfm.mit.edu> 
with body
	send usenet/news.answers/jpeg-faq/part1
	send usenet/news.answers/jpeg-faq/part2


================
RELATED SOFTWARE
================

Numerous viewing and image manipulation programs now support 
JPEG. (Quite a few of them use this library to do so.) The JPEG 
FAQ described above lists some of the more popular free and 
shareware viewers, and tells where to obtain them on Internet.

If you are on a UNIX machine, we highly recommend Jef Poskanzer's 
free PBMPLUS software, which provides many useful operations on 
PPM-format image files. In particular, it can convert PPM images 
to and from a wide range of other formats, thus making 
cjpeg/djpeg considerably more useful. The latest version is 
distributed by the NetPBM group, and is available from numerous 
sites, notably 
<ftp://wuarchive.wustl.edu/graphics/graphics/packages/NetPBM/>.
Unfortunately PBMPLUS/NETPBM is not nearly as portable as the 
IJG software is; you are likely to have difficulty making it 
work on any non-UNIX machine.

A different free JPEG implementation, written by the PVRG group 
at Stanford, is available from 
<ftp://havefun.stanford.edu/pub/jpeg/>. This program is designed 
for research and experimentation rather than production use; it 
is slower, harder to use, and less portable than the IJG code, 
but it is easier to read and modify. Also, the PVRG code supports 
lossless JPEG, which we do not. (On the other hand, it doesn't do 
progressive JPEG.)


================
FILE FORMAT WARS
================

Some JPEG programs produce files that are not compatible with our 
library. The root of the problem is that the ISO JPEG committee 
failed to specify a concrete file format. Some vendors "filled in 
the blanks" on their own, creating proprietary formats that no 
one else could read. (For example, none of the early commercial 
JPEG implementations for the Macintosh were able to exchange 
compressed files.)

The file format we have adopted is called JFIF (see REFERENCES). 
This format has been agreed to by a number of major commercial 
JPEG vendors, and it has become the de facto standard. JFIF is 
a minimal or "low end" representation. We recommend the use of 
TIFF/JPEG (TIFF revision 6.0 as modified by TIFF Technical Note 
#2) for "high end" applications that need to record a lot of 
additional data about an image. TIFF/JPEG is fairly new and not 
yet widely supported, unfortunately.

The upcoming JPEG Part 3 standard defines a file format called 
SPIFF. SPIFF is interoperable with JFIF, in the sense that most 
JFIF decoders should be able to read the most common variant of 
SPIFF. SPIFF has some technical advantages over JFIF, but its 
major claim to fame is simply that it is an official standard 
rather than an informal one. At this point it is unclear whether 
SPIFF will supersede JFIF or whether JFIF will remain the de-facto 
standard. IJG intends to support SPIFF once the standard is frozen, 
but we have not decided whether it should become our default output 
format or not. (In any case, our decoder will remain capable of 
reading JFIF indefinitely.)

Various proprietary file formats incorporating JPEG compression 
also exist. We have little or no sympathy for the existence of 
these formats. Indeed, one of the original reasons for developing 
this free software was to help force convergence on common, open 
format standards for JPEG files. Don't use a proprietary file 
format!


=====
TO DO
=====

The major thrust for v7 will probably be improvement of visual 
quality. The current method for scaling the quantization tables 
is known not to be very good at low Q values. We also intend to 
investigate block boundary smoothing, "poor man's variable 
quantization", and other means of improving quality-vs-file-size 
performance without sacrificing compatibility.

In future versions, we are considering supporting some of the 
upcoming JPEG Part 3 extensions--principally, variable 
quantization and the SPIFF file format.

As always, speeding things up is of great interest.

Please send bug reports, offers of help, etc. to 
jpeg-info@uunet.uu.net <mailto:jpeg-info@uunet.uu.net>.
