Mail Universal Groups vs Mail Non-Universal Groups

nmigjesus used Ask the Experts™
I need you help in some questions.
I have 2 domains in 2 cross forest and have one stucture of Exchange 2K3, and Exchange 2K7 in another.
In Exchange 2K7 I have migrating every account and groups. The groups still are in Global Distribution (Mail Non-Universal Group).
Before I begin migration of another domain, I want to know if i should change the type of Distribution Groups to Universal, because i have users and local groups from AD of Exchange 2K7 that need to add in Distribution Groups of domain of Exchange 2K3.
I want too know de positives and negatives things about Mail Non-Universal Group and Mail Universal Group.
Thanks a lot.
Nuno Jesus
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®
In short, it would be best for them to be universal groups. If they're not then you can get into all sort of trouble - mainly that distribution lists from one domain cannot bet expanded by user in the other domain, etc.
One caveat: you need to make sure that your (active directory) domain- and forrest functional levels are (at least) 2003.

Once migrated non-universal groups will work fine, you simply need to modify them in active directory rather than in the Exchange management console. When right clicking on them you will have a choice to convert them if you like. Converting them will allow you to manage them in exchange.

For a run down of the difference between the two see:
Michael B. SmithManaging Consultant

Sorry, I changed blogging platforms a couple of years ago. The above link is dead. This is a working link and the current recommended solution:

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial