When you use the Add or Remove Programs
item in Control Panel to uninstall a security update for Microsoft SQL Server 2005, the Windows Internal
Database (WYukon) is removed.
This problem occurs when you uninstall the security update for SQL Server 2005 GDR that is dated February 10, 2009.
For more information about the security update, click the following article number to view the article in the Microsoft Knowledge Base:
MS09-004: Description of the security update for SQL Server 2005 GDR: February 10, 2009
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.