Sharing Violation Error

When I try to load an assembly in 2009 SP2.1 the assemblygets loaded with various parts and sub assemblies suppressed. Whentrying to open the suppressed elements I get a "Cannot load part,Sharing Violation" message.

Our IT guy figures it's a recent security patch from Windows andnot the network.
The OS is XP SP3 32 bit.

Any help would be appreciated.

Thanks, JeremySolidworksGeneral