Thanks, Vic. That may have been the problem, I'm not sure.
First I tried deleting records in FOXUSER which appeared to be related to the Debugger... still had same problem. Deleting (actually renaming) the FOXUSER files did the trick, though.

As far as I know, there was no running timer, that is, I invoked Debugger the instant VFP loaded, before anything else...

Not too pretty, but this worked.

Than