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"

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

322756 How to back up and restore the registry in Windows

To have us work around this problem for you, go to the "Fix it for me" section. If you prefer to fix this problem yourself, go to the "Let me fix it myself" section.

Fix it for me

To fix this problem automatically, click the Fix it button or link. Then click Run in the File Download dialog box, and follow the steps in the Fix it wizard.

Notes

• If the problem that is described in this article still exists after you install the service pack or the hotfix, you must run this package again to work around this problem.
• This wizard may be in English only. However, the automatic fix also works for other language versions of Windows.
• If you are not on the computer that has the problem, save the Fix it solution to a flash drive or a CD and then run it on the computer that has the problem.

Then, go to the "Did this fix the problem?" section.

Let me fix it myself

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
   
   NoteThe 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.

Did this fix the problem?

• Check whether the problem is fixed. If the problem is fixed, you are finished with this section. If the problem is not fixed, you can contact support.
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