Quitting Excel using VBA causes run-time error 424

Answer 1

Add a call to ActiveWorkbook.Close to ExitWithoutPrompt:

Sub ExitWithoutPrompt()
    MsgBox "You failed to select a file, therefore Excel will now close.  Please refer to the readme file."
    Excel.Application.DisplayAlerts = False
    Excel.Application.Quit
    ActiveWorkbook.Close False
End Sub

This works for me under Excel 2003.

For some reason, the order of calling Application.Quit and ActiveWorkbook.Close is important. Counter-intuitively, at least to me, if you call ActiveWorkbook.Close before Application.Quit you still get the error.