[hugepickle]

I currently have BES deployed with the mailbox on a 2003 server and the BES server is running the Exchange 2003 management tools. I am going to be migrating to Exchange 2007 and there will be a period of co-existence during which some blackberry users will be on 2003 am some on 2007. I want to ensure that users on both versions of Exchange can continue to use their blackberries throughout that time. Exchange 2007 is currently installed but there are no mailboxes on it yet.

I have heard that if I follow the instructions from blackberry (KB14502 on Blackberry's web site) that once this is completed the blackberry users on 2007 will be able to use their devices but those on exchange 2003 will not. Can someone who has done this confirm if this is correct? If so, can someone please provide the appropriate steps on how to migrate for coexistence scenario like this?

[knottyrope]

CDO 1.2.1 is backwards compatable with exchange 2003.

You dont have to move all mailboxes at once, just skip that step in the KB and move when you want.

[CanuckBB]

You will need CDO 1.2.1 once the besadmin account is migrated to 2007. Until then, nothing needs to change on the BES. both coexist and as mentioned before 1.2.1 is backwards compatible.