I have two users who get "Verification of S/MIME component failed" upon starting GW.

I have tried everything I have found in the forums and TID's, most notably checking these two files: GWMIM1.OCX and GWMIM1.MD5 and copying them straight from the install directory to the client machine. The problem still existed.
Then I uninstalled, made sure the groupwise folder was deleted and reinstalled and the problem persists.

What else could be causing this error on startup?