Error message when you install SQL Server 2005 or SQL Server 2008: "The file C:\Windows\Microsoft.NET\Framework\[version_number]\mscorlib.tlb could not be loaded"

Problem:
The file C:\Windows\Microsoft.NET\Framework\version_number\mscorlib.tlb could not be loaded. An attempt to repair this condition failed because the file could not be found. Please reinstall this program.

Workaround:

For SQL Server 2005

To work around this problem, you must manually specify the correct path of the Mscorlib.tlb file in the registry. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate the following registry subkey:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\90\Tools\Shell\TlbAutoRepair\mscorlib.tlb

   Notes

   • If you install SQL Server 2005 on 64-bit operating systems, locate the following registry subkey:

     HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SQL Server\90\Tools\Shell\TlbAutoRepair\mscorlib.tlb

   • If you install SQL Server 2005 Express Edition with Advanced Services, locate the following registry subkey:

     HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\90\Tools\ShellSEM\TlbAutoRepair\mscorlib.tlb

3. In the right pane, double-click the registry entry TlbPath. The Edit String dialog box appears.
4. In the Value data box, replace %CLRVERSION% with the following value:

   v2.0.50727

   Note The value v2.0.50727 indicates the version of the .NET Framework that the original release version of SQL Server 2005 uses.

5. Click OK, and then exit Registry Editor.

Important If you install a SQL Server 2005 service pack or hotfix, the service pack or hotfix will change the value that you replace in step 4 back to %CLRVERSION%. If the problem that is described in this article still exists after you install the service pack or the hotfix, you must following these steps again to work around this problem.

For SQL Server 2008

To work around this problem, you must manually specify the correct path of the Mscorlib.tlb file in the registry. To do this, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. Locate the following registry subkey:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\100\Tools\Shell\TlbAutoRepair\mscorlib.tlb Notes

   If you install the 32-bit version of SQL Server 2008 on 64-bit operating systems, locate the following registry subkey:

   HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Microsoft SQL Server\100\Tools\Shell\TlbAutoRepair\mscorlib.tlb

   If you install SQL Server 2008 Express Edition with Advanced Services, locate the following registry subkey:

   HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\100\Tools\ShellSEM\TlbAutoRepair\mscorlib.tlb

3. In the right pane, double-click TlbPath.
4. In the Value data box, replace %CLRVERSION% with the following value:

   v2.0.50727

   Note The value v2.0.50727 indicates the version of the .NET Framework that the original release version of SQL Server 2008 uses.

5. Click OK, and then exit Registry Editor.

Important If you install a SQL Server 2008 service pack or hotfix, the service pack or hotfix will change the value that you replace in step 4 back to %CLRVERSION%. If the problem that is described in this article still exists after you install the service pack or the hotfix, you must following these steps again to work around this problem.

More Info:
http://support.microsoft.com/kb/918685/en-us