To actually remove the buttons requires extensive coding using the API, but this procedure will disable the close button, having th esame effect:
Private Sub UserForm_QueryClose(Cancel As Integer, CloseMode As Integer)
If CloseMode = 0 Then Cancel = True
End Sub
Just place that code in the userform codepane. It also disables Alt-F4, and effectively means that the form can only be dismissed by code.
A.C.