Microsoft KB Archive/250867

Knowledge Base

Cannot Install Service Pack 6/6a with High Encryption Internet Explorer

Article ID: 250867

Article Last Modified on 11/1/2006

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APPLIES TO

• Microsoft Windows NT Server 4.0, Terminal Server Edition Service Pack 6
• Microsoft Windows NT Workstation 4.0 Developer Edition
• Microsoft Windows NT Workstation 4.0 Developer Edition
• Microsoft Windows NT 4.0 Service Pack 6
• Microsoft Windows NT 4.0 Service Pack 6a
• Microsoft Windows NT 4.0 Service Pack 6
• Microsoft Windows NT 4.0 Service Pack 6a

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This article was previously published under Q250867

SYMPTOMS

If you attempt to install the standard-encryption (or 56-bit) version of Windows NT 4.0 Service Pack 6 or 6a on a Windows NT 4.0-based computer that already has Microsoft Internet Explorer High Encryption Pack or Internet Explorer version 5.5 installed, you receive the following error message:

You have chosen to install a version of the Service Pack with Standard Encryption onto a system with High Encryption. This is not supported. To successfully install this version of the Service Pack, you must install the High Encryption version. Press Help for more information about obtaining the High Encryption Version of this Service Pack. Service Pack Setup will now exit.

CAUSE

This issue occurs because the Schannel.dll file that is installed by Microsoft Internet Explorer High Encryption Pack and Internet Explorer 5.5 cannot be overwritten by the service pack installation program.

Internet Explorer 5.5 includes 128-bit encryption by default because of the United States government's recent decision to allow companies to export products that use strong, 128-bit encryption.

Windows NT 4.0 Service Pack 6 and 6a were released before this decision was made. Therefore, localized versions of Service Pack 6 and 6a are 40-bit versions. 40-bit versions of these service packs detect higher encryption levels and do not allow themselves to be installed.

RESOLUTION

To work around this issue and prevent the version-number scanner from comparing the Schannel.dll file versions:

1. Use any text editor (such as Notepad) to open the Update.inf file in the I386\Update folder in the service pack source files.
2. Place a semicolon (;) before the reference to the Schannel.dll, Security.dll, and Ntlmssps.dll files in the [CheckSecurity.System32.files] section of the Update.inf file.
3. Save and then close the Update.inf file.
4. Install the service pack.

Additional query words: 56 bit sp6 sp6a 128bit install 128

Keywords: kberrmsg kbsetup kbprb KB250867

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