UF Textbox8 PLZ = Textbox9 = Ort

Private Sub TextBox8_AfterUpdate()
   Dim varRes As Variant

   If IsNumeric(TextBox8) Then
      With Sheets("Postleitzahlen")
         varRes = Application.Match(CDbl(TextBox8.Text), .Range("A2:A20000"), 0)
         If IsNumeric(varRes) Then
            TextBox9 = Application.Index(.Range("B2:B20000"), varRes)
         Else
            TextBox9 = "PLZ '" & TextBox8 & "' nicht gefunden"
         End If
      End With
   Else
      TextBox9 = "Falsche Eingabe"
   End If
End Sub