....
 
If fso.FolderExists("C:\ab") Then
Set Folder1 = fso.GetFolder("ab")
End If
If fso.FolderExists("C:\cd") Then
Set Folder2 = fso.GetFolder("C:\cd")
End If
If fso.FolderExists("C:\ef") Then
Set Folder3 = fso.GetFolder("C:\ef")
End If
If fso.FolderExists("C:\gh") Then
Set Folder4 = fso.GetFolder("C:\gh")
End If
 
 
    Ergebnis = FormatBytes(Folder1.Size + Folder2.Size + Folder3.Size + _
      Folder4.Size)
    Text3.text = Ergebnis