1, It depends whether you want it to be a security group or just a distribution group
2. You can't - they are both the same.

Hi Zelandakh,

Noted.
Thank you for your time and help.

with regards,
SC Moh

In general, you can't lose by having it be a security group. I've even seen distro groups get created that don't show up in the Offline Address Book. Change them to a security group, and boom, they show up.

Dave Shackelford
ThirdTier.net
TrainSignal.com

Hi ShackDaddy,

Thank you for your note.

Do you know the permission (security) for exchange server objects (exchange servers, exchange trusted subsystem, exchange domain servers, etc...) in active directory OU of server 2008?

Please advise.

with regards,
SC Moh

No, I don't offhand.

But it's important if you are having issues with a mailbox that you check the user's security properties (enable Advanced view in Active Directory Users and Computers) and in the Advanced section make sure that the checkbox for inheriting permissions is checked, otherwise many Exchange-related things will not work properly for that particular user. Any time a user is made a member of Domain Admins for more than 10 minutes, it will cause that box to be unchecked, and it will never "recheck" itself. So even if you did it as part of troubleshooting three years ago, it may cause a problem today.

Dave Shackelford
ThirdTier.net
TrainSignal.com