You must uninstall all interim updates before you install Exchange Server 2010 Service Pack 2
Topic Last Modified: 2011-11-02
The Microsoft Exchange Best Practices Analyzer Tool checks whether a Microsoft Exchange Server 2010 interim update (IU) is installed on the computer that is running Exchange 2010. If an IU is installed, Microsoft Exchange Server 2010 Service Pack 2 (SP2) cannot be installed.
To install Exchange 2010 SP2, you must uninstall the IU. After the IU is uninstalled, install Exchange 2010 SP2.
To uninstall the IU, follow these steps:
In Control Panel, double-click Programs and Features.
In the Currently installed programs list, click Interim Update for Exchange Server 2010 (KBxxxxxx), where xxxxxx is the Knowledge Base article number that is associated with the IU.
At a command prompt, run sn.exe -Vu * to enable strong name verification.
Run sn.exe –Vl to verify that strong name verification is enabled.