setfocus sometimes gets error 2110
 

I have a multitab form that I have some validation on that checks to see if a
control in the first page has been filled in when the next tab is selected.
If it's not, then it shows a message box moves back to the page that the
empty textbox was on and then set the focus back to that control.

I works OK... on some computers. On others I get an error 2110, cannot
setfocus becase control is hidden, cannot accept focus...

Some of the computers it doesn't work on are on a network so we ran it under
administrator on the local profile and it still didn't work. It wors on
Windows XP sometimes and not on other Windows XP computers All are running
Office XP. It alao works on a Windows 2000 computer.

Of course the machines that it runs on are not the ones I need it to run on.

Thanks for any help