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Sub columnistgleich()

Dim arrdata, arrbase, serg$, arrerg
Dim i&, cnt&, ii&

arrbase = Intersect(ActiveSheet.UsedRange, ActiveSheet.Columns("C"))
arrdata = ActiveSheet.UsedRange

For i = 1 To UBound(arrdata, 2)
  For cnt = 1 To UBound(arrbase)
     If arrbase(cnt, 1) <> arrdata(cnt, i) Then Exit For
  Next
  If cnt > UBound(arrbase) Then serg = serg & i & ","
Next

If Len(serg) > 0 Then serg = Left(serg, Len(serg) - 1)

With Worksheets.Add(after:=Worksheets(Worksheets.Count))
 .Name = "Ergebnis"
 .Range("A1") = "Übereinstimmende Spalten (Spaltennummer)"
 
 arrerg = Split(serg, ",")
 .Range("A2").Resize(UBound(arrerg) + 1).Value = Application.Transpose(arrerg)
 
End With
End Sub