In the address box when setting up the connection to your exchange server make sure of the folowing.
Can you access your exchange webmail by typing in the folowing address into a web browser?
http://www.yourdomainname.com/exchange
If you can access it then in the server field on the connections tab on the phone type that exact same address.
For some reason on windows mobile 6.1 you cant just type the ip address of the server running exchange.
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