We're running Exchange 2010 w/ Outlook 2010 and 2 forests with full trusts between them. We have a few domain local mail enabled security groups for reasons I'd rather not get into here :) Regardless, I've noticed these groups do not show group membership at all in the OAB. In the GAL and Webmail, they show the members from our Forest, but not from the other Forest. So two questions: 1. Is it possible for the OAB to retrieve membership information from domain local groups? 2. Is it possible for the GAL to display the members from the other forest? The GAL in Outlook doesn't show them at all, but in Webmail they each get a (None) entry. Thanks, Matt

Hello Matt, I think this is because Exchange distribution group cannot find the user (outside the forest). In Exchange 2010, you cannot set Exchange to view users in another forest. You can go to check the members of distribution group (in EMC), you will see the users (in another forest) show as user SID, the distribution group cannot find the object. If you want users( in another forest) can be shown in the distribution group, one workaround is to create mail contacts (or mail user)for that users (in another forest), then add the contacts to the distribution group. Thanks, EvanEvan Liu TechNet Community Support

Hello Matt, I think this is because Exchange distribution group cannot find the user (outside the forest). In Exchange 2010, you cannot set Exchange to view users in another forest. You can go to check the members of distribution group (in EMC), you will see the users (in another forest) show as user SID, the distribution group cannot find the object. If you want users( in another forest) can be shown in the distribution group, one workaround is to create mail contacts (or mail user)for that users (in another forest), then add the contacts to the distribution group. Thanks, EvanEvan Liu TechNet Community Support