DOCUMENT:Q242286  30-JUL-2001  [winnt]
TITLE   :BETA-HOWTO: Update an Existing Windows 2000 Migration DLL
PRODUCT :Microsoft Windows NT
PROD/VER:WINDOWS:
OPER/SYS:
KEYWORDS:kbsetup kbmigrate kbOSWin2000 kbSDKPlatform kbMigWin9xtoWin2k kbMigrationDLL kbFAQ kbDS

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The information in this article applies to:

 - Microsoft Windows 2000 Advanced Server 
 - Microsoft Windows 2000 Server 
 - Microsoft Windows 2000 Professional 
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SUMMARY
=======

A Windows 2000 Migration DLL can be installed on your Windows 95/98 computer by
installing the Migration DLL in its own directory and pointing to it from the
registry. Windows 2000 setup automatically calls the Migration DLL if you ever
decide to upgrade to Windows 2000 Professional. After installing an
application's Migration DLL, how can any updates or changes to the Migration DLL
be made on that computer?

The best strategy is to make the updated Migration DLL available on a Web site
for download. Although you could write a setup to find and replace the existing
Migration DLL, this is unnecessary. Instead, use the DLLVersion parameter in the
QueryVersion function to increase the version of the new Migration DLL. You can
then place this Migration DLL in any directory on the computer. You point to
this new Migration DLL when setup requests Upgrade Packs. When Windows 2000
Setup calls two Migration DLLs that return the same ProductId, Setup then checks
the number returned by DLLVersion. Setup will only continue to process the
Migration DLL with the higher version number. The higher DLLVersion number on
the new Migration DLL prevents the original DLL from processing.

REFERENCES
==========

For more information on Migration DLLs, see following in the MSDN Library:

   Platform SDK; Management Services; Setup; Migration-Extension Interface

Additional query words:

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Keywords          : kbsetup kbmigrate kbOSWin2000 kbSDKPlatform kbMigWin9xtoWin2k kbMigrationDLL kbFAQ kbDSupport kbGrpDSTools kbMigrationDLLFAQ 
Technology        : kbwin2000AdvServ kbwin2000AdvServSearch kbwin2000Serv kbwin2000ServSearch kbwin2000Search kbwin2000ProSearch kbwin2000Pro kbWinAdvServSearch
Version           : WINDOWS:
Issue type        : kbinfo

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