The same problem was discussed once on Russian forum. I forgot the solution proposed, but Fred's is simple one.

It looks like a bug in VFP.

>Thanks- that worked. I'm still perplexed as to why this should happen. Is it indeed because the form and the MessageBox are both modal? If so, why on earth should that affect the _SCREEN.Closable setting? How is it being affected? I'd love to know why this happens. But I'm also more than a little happy to have a workaround, so I'll count my blessings.
>
>Thanks again.
>
>Henry