ISA Server 2006 Run time error 11004

Hi Everyone,
I have a question related to ISA Server 2006. Hope there are professionals who can solve the problem which I am facing.
The server is new and already configured but my clients can not send and save files for upload. When trying to save file for upload an error occurs.
Error: Run time error 11004. No data record for requested type.
I would be very glad if anyone can help me to get rid of this error.
Thanks!
