That works great!! Thanks!

Here is shorter UDF which will function the same as the one James posted...

Function IDKiller(ByVal S As String) As String
Dim X As Long
For X = 1 To Len(S)
If Mid(S, X, 10) Like "##########" Then
Mid(S, X) = "XXXXXXXXXX"
Exit For
End If
Next
IDKiller = S
End Function

Rick Rothstein (MVP - Excel)