Migrated users to a new BES server (4.1 -> 5.0) a few days ago and all was fine. Moved a few users to a new Exchange server (2003 -> 2010) and now some of those moved users cannot send or receive email. BES is working for other users. Not really sure where to look or to make sure BES is talking to Exchange 2010 SP1 correctly.
CDO version is 6.5.8211.0