Jim,

I tried every possible combination of LockScreen with no luck. I just put it down to another 'listbox in toolbar' anomaly that I've run into. Maybe its a VFP 5 thing, but listboxes exhibit some weird behaviour in toolbars. In the end I opted for the LockWindowUpdate call (or focus.fll's rendition) and now the interface is smooth as silk.

Thanks for your input.

Dale