Do you mean when you start a Function you can't access the other Buttons until it's Finished Processing?

If so, insert a call to DoEvents in your Function, eg.
Code:
Private Sub cmdStop_Click()
    cmdStop.Tag = "X"
End Sub

Private Sub cmdStart_Click()
    Dim iCount As Long
    cmdStop.Tag = ""
    While Len(cmdStop.Tag) = 0
        iCount = iCount + 1
        Caption = iCount
        DoEvents
    Wend
End Sub

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Aaron Young
Analyst Programmer
[email protected]
[email protected]