I am having a problem getting my User Form to Initialize.

3 Days ago the Code was fine and opened and ran fine. Nothing in the code
has changed, but now trying to open the User Form Locks up Excel. If you open
Excel and then open the User Form Workbook, Click on the Page to display the
User Form Excel Locks up.

Now repeat the same steps, but this time open the VBA Editor first, then
display the User Form, it runs fine. Has anyone else had this Problem with
Office 2007? If so how can I fix it?

Code on the Worksheet Page:
Private Sub Worksheet_SelectionChange(ByVal Target As Range)
UserForm1.Show
End Sub


Code in the User Form Code Window.
Private Sub UserForm1_Initialize()

'================================================= ===
'Written Office
With Me.Address_21
.AddItem "AA"
.AddItem "AB"
.AddItem "AC"
.AddItem "AD"
.AddItem "AE"
End With
'================================================= ==
'Engineer
With Me.Engineer_2
.AddItem "AF"
.AddItem "AG"
.AddItem "AH"
.AddItem "AJ"
.AddItem "AK"
.AddItem "AL"
End With
'================================================= ==
' Equipment Engineer
With Me.Engineer_3
.AddItem "AM"
.AddItem "AN"
.AddItem "AP"
.AddItem "AQ"
.AddItem "AR"
End With

End Sub