>> Can you test on a different computer with a different mouse/mouse driver? Just to eliminate any chance it's hardware/driver related.

Can reproduce on development machine and also in compiled .EXE on a number of test machines.

>>It sounds like some part of the mouse operation isn't completing or an event isn't being cleared, and that's affecting the called form. >>I believe there's a mouse equivalent of CLEAR TYPEAHEAD but I can't find it in a quick search. It may be worth a try.

This was one of my earlier thoughts and I have added CLEAR TYPEAHEAD, I can't find a mouse equivalent, I don't think there is one.

>>Another thing that has tripped me up from time to time is putting test code in various events/methods and neglecting to include >>DODEFAULT(), or inadvertently causing it not to be fired. If you have related events like MouseDown/MouseMove/MouseUp this >>might cause weird effects.
Will Double, Double check!

>>A SWAG, since you're using ActiveXs have you experimented with AutoYield?
Have tried different AutoYield settings and also removing the ActiveX controls completely, makse no difference.

>>Is LockScreen being toggled anywhere? Any ON KEY LABELs in effect?
Checked it in debuger and put a breakpoint on it and it does not get changed.

>>Is there any unique code being fired by the calling form before it loses focus? Anything weird in there?
Nope, and in fact the working route and the problem route end up launching the form from the same method.

Thanks for all your help

Gary.