In some cases there is an issue with installing the following update “Security Update for Microsoft Visual Studio 2008 Service Pack 1 (KB971092)”. The workaround to properly install the update you must set the security on the files vsvars32.bat and vcvarsall.bat to allow the local Users group write permission on those files. I am not sure why this is an issue but from reading other posts and such on the issue most of the affected people do not have vc++ installed.
They can be found in the following folders:
x86
x64