Hi, I have exchange in one domain (a1)and all users in another domain (a2). a1 and a2 domain in the same forest. I have 5 remote sites all in a2 domain each site hasa DC/GC. Exchange in the center site has its own DC/GC. Right now, the exchange only can see the DC/GCs at the center site as well as the parent dc/gc. it is not able to see any DC/GC at remote site in a1 domain.I wonder if i should add trust between a1 and a2 domain. if not how can i fix this problem.ThanksLy

Hi,Trust is already there if the domains are members of the same forest.This sounds more like an AD or DNS problem.What issues are you seeing apart from this?Is AD replicating properly?Can you add users from the child domain to a group in the root domain (means that AD's can see each other?Leif

hi ,let suppose you have a root domain abc.com and u have a child domain "child1.abc.com" and another domain "child2.abc.com inthe single site" and all these domain controllers are present in site A.your exchange serverare also in this site A "child.abc.com" and exchange utilizes global catalog of its own sites it Shows the global catalog of1)abc.com2)child1.abc.com3)child2.abc.combecause they are all in the same site A.regardsSyed Arsalan .syed.arsalan

As syed suggested Exchange will use Global Catalog servers in the local Active Directorysite. Exchange 2007 will also use only GC that is running minimum W2003 SP1. check the application log for 'MSExchange ADAccess' events on your Exchange servers, they will tell you what DC/GC they use.

Hello Ly, Exchange will use local site GCs firstly, local domain is preferred. That means if no domain a1 GC in the same site with Exchange. Exchange will use a2 GC, except all in-site GCs are failed, Exchange will not choose GCs in another site. I suggest you check event 2080 in event viewer, see if you could see the a1 GC there. http://support.microsoft.com/default.aspx/kb/316300 The KB is for Exchange 2000 and 2003, in Exchange 2007, we don't need to increase the diagnostics logging level and we could check the result directly. Thanks, Elvis