SetFocus Error in Windows XP

Has anyone else ran into problems with Windows XP throwing error 5 (Invalid procedure call or argument) when running a VB6 app in Windows XP. One of my programs is occasionally throwing that error. But it only happens on Win XP machines and it is not consistent in throwing it.
On another site a guy was talking about this like it was an acknowledged problem, but I didn't find anything about it in Microsoft's Knowledge Base. Does any one here know anything about it?

Try:-

VB Code:

Public Sub SafeSetFocus(Byval ctlIn As Control)
 
If ctlIn.Visible And ctlIn.Enabled Then
    ctlIn.SetFocus
End If
 
End Sub

The control is visible and enabled. The error has never occurred outside of Windows XP. It does not occur on every setfocus in the program when run under XP. It's almost like a random (and changing) number of calls to setfocus causes the error.

I get this too, but differently: I get it when there are timers running when I bring up a Message Box.