I have noticed that about every third time or so I start up the VB6 IDE, a message box appears with the following error message:-
Method \'~\' of object \'~\
I used to occasionally run into this error and, in my case, it was caused by the Visual Source Safe add-in (bad install I guess; re-install corrected the issue). It never caused a problem; it was just a bother. As Jon stated in the comments, I would try shutting off add-ins to see if that fixes the issue. Another thing is to make sure you are running Service Pack 6.