Grigore,
It's not inexplicable.
It's not the Control.Visible property, it was the Form.LockScreen that was causing your problem. It prevents the proper repainting of the form. A control will repaint itself when it gets focus.
If a control's .Visible property is set to .F. the control is removed from the event loop so there's no way you could click it or keyboard to it.
>Yes. The .Visible property was set .T. And no, I don't have any ActiveX controls there. Anyway, in the mean time I've deleted those forms (2) and builded them from scratch. And that weird behavior stopped.
>
>Thank you for involving. You know when VFP start doing inexplicable things?