Excel VBA Retrieving a Specific Pattern from String
You can remove a goto - unconditional branches are strongly discouraged and in this case the code fall-through renders it unnecessary.

    If x = 0 Then
        GoTo NextIteration
    Else
        cell.Offset(0, 1).Value = Mid(cell.Value, x, 13)
    End If

NextIteration:


becomes

If x &lt;&gt; 0 Then cell.Offset(0, 1).Value = Mid(cell.Value, x, 13)


This code only works for a specific (hard coded) pattern without any variations. Your example (test case) focuses on numbers, but your pattern also matches aa.bb.ccc.ddd.