Well, isn't this fun!

I have found bizarre, unexplainable behavior with Access in the past, and now I have a new item to add to the list.

Previously, I was using the built-in VBA debugger to check the values that were being seen by the various routines. I would put my cursor over a variable to see the tooltip that showed that variable's value.

I was creating an example database for you guys to check out, and accidentally "fixed" the problem.

When I added a quick MsgBox to the routine that contained the DoCmd.OpenForm, the problem went away! Even after I deleted the MsgBox line (so my code was identical to the "problem" code), the problem was now gone.

Well, at least it's working now!