Question : OUTLOOK 2003 is not working with ISA 2006

I downloaded a trial version of windows 2003 enterprise edition R2 and I have installed ISA 2006 also trial version .
I have joined my ISA server to the Domain server and all client is browing internet by assigning the ip of isa server as proxy server and the gate way.
But all clients are not able to use outlook  which they were able to use when ISA not installed.
I have done the follwoing to solve the problem but it is still not working:
chaning outlook from 1 to zero in setting of ISA.
I have enable DNS as first Rule .
enable pop3 and Smtp as second rule.
enable every thing as third rule.

Do you have any idea how to solve this?

Answer : OUTLOOK 2003 is not working with ISA 2006

Have you looked at the following article?
http://support.microsoft.com/default.aspx?scid=kb;en-us;302357