To work around this problem, examine the list of values for the following subkeys in Registry Editor:
Gacutil.exe cannot override Windows Installer reference counts. Several possible causes of conflict exist between Windows Installer and Gacutil.exe. If you use Windows Installer to install an assembly in the GAC, Gacutil.exe may not be able to remove the assembly.
Article ID: 873195 - Last Review: 13 May 2009 - Revision: 1