I had this problem once, in my case I had a listbox bound to a table and my screen had the ability to change folders to another dataset. The form would then only show some of the controls and miss others during the refresh, nothing I could do would fix this until I unbound the listbox and freed it from the table. The same thing happened with a grid, it would seem that if you close the table that the control is bound to then re-open it or open another one, you can't get the control to refresh. Interestingly it also affects some other controls as well for no apparent reason
Cheers
John