Global Scup As Boolean
Global Ebes As Boolean
Global Cclt As Integer
Option Explicit
Sub DateienLesen()
    Scup = Application.ScreenUpdating
    Ebes = Application.EnableEvents
    Cclt = Application.Calculation
    Call EventsOff
    Dim DateiName As String
    DateiName = Dir("C:\Temp1\" & "*.xls")
    Do While DateiName <> ""
        If ThisWorkbook.Name <> DateiName And Len(DateiName) > 11 Then
            Workbooks.Open Filename:="C:\Temp1\" & DateiName
            Workbooks(DateiName).Worksheets("Tabelle1").Copy Before:=Workbooks(ThisWorkbook.Name).Worksheets(1)
            ActiveSheet.Name = Mid(Right(DateiName, 12), 1, 8)
            Workbooks(DateiName).Close
        End If
        DateiName = Dir
    Loop
    Call EventsOn
End Sub

Public Sub EventsOff()
    With Application
        .ScreenUpdating = False
        .EnableEvents = False
        .Calculation = xlCalculationManual
    End With
End Sub

Public Sub EventsOn()
    With Application
        .ScreenUpdating = Scup
        .EnableEvents = Ebes
        .Calculation = Cclt
    End With
End Sub