>Issuing DOEVENTS every hundred records in a scan works somewhat. The WAIT WINDOW message does not freeze, but the screen becomes dimmed as it does in Windows 7 whem app is not responding. BTW, the Debugout message does not show until the end of the cycle, when all the messages show up at once.

I have a few processes like that, and generally I output a line now and then (echo the logging of a few things) to _screen or a blank form. So you have a progress indicator and there's something going on and the Windowses may be somewhat happier than without it.

In cases where I suppress the output but rely solely on wait window, just clicking out of this exe and back to it brings on the exactly same behavior as you describe. The task is seemingly frozen, Windows thinks it's not responding, new wait window commands don't show up, yet the task eventually gets done.