系统是Windows Server 2008 R2,补丁Windows Internal Database Service Pack 4 x64 Edition (KB2463332)总是安装失败，Windows Update中显示错误代码 643，事件查看器中显示：
Product: Windows Internal Database -- Error 29528. The setup has encountered an unexpected error while Setting Internal Properties. The error is: 安装时发生严重错误
最后在http://technet.microsoft.com/en-us/library/cc708610%28v=ws.10%29.aspx中找到解决办法，原文如下：
Windows Internal Database -- Error 29528
I also encountered Windows Internal Database -- Error 29528. I found an easier solution. See http://support.microsoft.com/kb/919945 . Search the registry for SQLGroup to find the subkeys. Then empty the key value (delete the SID, not the subkey). My server only had the SQLGroup and FTSGroup keys to clear. Then run the update again. The update will install correctly, and it will put the correct SID into the two subkeys.
5/7/2011
就是照http://support.microsoft.com/kb/919945中的办法将注册表中的某些项的值清空（不是删除项）：
- Start Registry Editor, and then locate one of the following registry subkeys:
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.2005\Setup
- HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server\MSSQL.X\Setup
Note Only one of these registry subkeys will exist on your computer.
- Empty the following registry entries:
- SQLGroup
- FTSGroup
- AGTGroup
提示：①按Win+R打开“运行”对话框，输入regedit可打开注册表编辑器