Code working on local machine (IIS Express) but not live on full IIS

Hi,
I have a Problem with the following code.
It works fine on the local machine (IIS Express 8) but not online on the live site (IIS 8)

If Request.QueryString("Ueberblick") <> "" Then...Select Case str_Ueberblick                Case "Weihnachtsbeleuchtung"                    Dim ContentDiv As Go to the complete details ...