Sub MultiCsvImport()
Dim dateien, i, lastrow
lastrow = 1
dateien = Application.GetOpenFilename _
("txt-Dateien (*.txt), *.txt", MultiSelect:=True)
If IsArray(dateien) Then
For i = 1 To UBound(dateien)
Workbooks.Open dateien(i), local:=True
With ThisWorkbook.Sheets(1)
ActiveSheet.UsedRange.Copy Destination:=.Range("A" & lastrow)
lastrow = .UsedRange.Rows.Count + 1
End With
ActiveWorkbook.Close False
Next i
End If
End Sub