Windows NT® 4.0 Service Pack 6a (SP6a) resolves the SP6 issue with Lotus Notes and other Winsock-based applications, and provides other updates to Microsoft Windows NT Workstation 4.0 and Windows NT Server 4.0 (including Enterprise Edition). Service Pack 6a contains known year 2000 updates for Windows NT 4.0. These year 2000 updates are also available as separate Web downloads that may be applied to a Service Pack 4 system. Providing these options gives organizations the flexibility to choose the best way to address year 2000 issues. SP6a is not a required upgrade for year 2000; Microsoft recommends that each customer consult the SP6a documentation and then determine whether to deploy it.

Note Service Pack 6a is available in Standard Encryption or High Encryption (128-bit) versions for both the Intel x86 and DEC Alpha platforms. Both versions contain the same updates and differ only in the level of encryption. If you have previously installed 128-bit components on your system, download the High Encryption version.

SP6a includes the following updates to SP6:

• The update for the SP6 issue with Lotus Notes and other Winsock-based applications. This issue prevents connecting to the server when the current user is not logged in with administrator rights. For more information this issue, read Microsoft Knowledge Base (KB) Article Q245678. (This site is in English.)
• In accordance with Microsoft's commitment to Year 2000 compliance, SP6a includes an update to the IIS 3.0 log converter utility, convlog. For more information this, read KB Article Q245329. (This site is in English.)
• Winver.exe has been revised to allow the user to verify quickly whether a system is running SP6a.

If you installed SP6 or SP6a between November 22 and November 29th, 1999, please confirm which Service Pack you have by following these steps. (This site is in English.) This is recommended because part of the SP6a pages were mistakenly posted on the Web before the SP6a binaries were released. If you already have SP6a installed, you do not need to take any action.

Warning To avoid problems, including possible data loss, if you use both Microsoft Outlook and Computer Associates Inoculan, you should verify that you are using the latest version of the Inoculan drivers before installing SP6a. Visit the Computer Associates Support Web site to obtain the latest drivers. (This site is in English.) Other applications and prior versions of Service Packs may be affected as well. For additional details, read KB article Q244652 (This site is in English.)

For more installation recommendations and additional information about SP6a, visit Windows NT 4.0 Service Pack 6a. (This site is in English.)

For documentation about SP6a including installation instructions and known issues, see the Readme file. (This site is in English.)

• 60 MB storage space. (If you want to have an uninstall directory, the storage space requirement increases to 120 MB.)
• No Service Pack requirements needed.
• Windows NT Workstation 4.0, Windows NT Server 4.0 or Windows NT Server 4.0, Enterprise Edition.

1. Click Start, point to Settings, and then click Control Panel.
2. Double-click Add/Remove Programs.
3. Select Windows NT 4.0 Service Pack 6a and then click Add/Remove to uninstall.