Option Explicit
Private Function GetMaxNummer() As String
Dim oFile As Object
Dim iNr As Integer, iMaxNr As Integer
Dim sPath As String
sPath = "D:\Test"
With CreateObject("Scripting.FileSystemObject").GetFolder(sPath)
For Each oFile In .Files
iNr = Val(Split(Split(oFile.Name, ".")(0) & "-", "-")(1))
If iNr > iMaxNr Then
iMaxNr = iNr
GetMaxNummer = Mid$(Split(oFile.Name, "-")(0) & "-" _
& Right$("000" & iMaxNr + 1, 4), 4)
End If
Next oFile
End With
End Function
Private Sub Workbook_Open()
With ThisWorkbook.Sheets("Tabelle1")
.Cells(7, 4).value = GetMaxNummer()
End With
End Sub