Hi jurgen007,

Please set the upload type to iframe and UploaderDebug to 1 and try again. What new error you get? What debug info you get from the debug window?

<CuteWebUI:Uploader ID="uploader1" runat="server" UploaderDebug="1" UploadType="IFrame">
        </CuteWebUI:Uploader> 

If your site is online, please post your uploader page url, so we can check it for you too. Also, you can send it to [email protected].

Regards,

Ken