Error while accessing CRM 4.0 in Windows Server 2008 Operating System
The fact is MSCRM 4.0 doesn't work with IPv6.
The fix for this is simple, open your hosts files
(
and add a line for your server name there with an IPv4 address. Save and ping again to make sure it is working.
Once it is, do an IISReset and it will be working!
Refrence site: http://www.sadev.co.za/node/170