I found an issue with using Listbox.Selected(i) in 2010 to test for any selected items. In the end I came up with this to be compatible between 2003 & 2010

[VBA]'Check for Selected; handle 2003 and 2010 versions
If IsNull(ListBox1) And ListBox1.Selected(1) = False Then
MsgBox "No item selected", vbExclamation
Exit Sub
End If[/VBA]