I am having a hard time here determining why I am unable to see my Global Address List when I have my Outlook Client (200) running in online mode.
A bit about my current setup, I have recently begun migrating things from Exchange 2003 and Windows Server 2003 to Exchange 2007 and Windows Server 2008. I currently have 4 AD servers and they are all running as Global Catalog servers. The idea is when this is running correctly to decommission the old 2003 servers and Exchange. However, when running the Outlook client in Online mode (ie. non-cached) I cannot see anything in the GAL. The interesting thing though, this only occurs when the client tries to connect to either two of my new 2008 AD servers. When connecting to the old 2003 servers, I can see everything like I am supposed to. (I say this is random as the Outlook client seems to use some type of round robin to determine which global catalog to connect to when the application starts.) I've migrated the FSMO roles, and also updated the policies to Exchange 2007. Through my mobile device it seems that I can access the GAL and also through OWA via the CAS machine there seems to be no problem viewing the list. I have also tried turning off the firewall on the AD machine itself to see if that could have been the problem, but it still has not fixed the problem.
Might anyone have any idea about where I should be looking to see what is causing this issue of my Outlook client not being able to view the global address list in online mode?