Hi, we are in the process of migrating all of our users from an Exchange 2003 environment to a 2010 environment.
I have searching around the web and these forums and it seems as though I can have the BES server serve users on both Exchange server simultaneously - is that correct?
I'm hoping that is the case, the reason for this is that I have approx 120 BB users on my BES, migrating these will take some time and I really need users on both servers to have full mail support while performing this task.
My BES is on version 5.0.3.31.
What I'm hoping to do is to migrate batches of users each night for a couple of weeks, say 12 users per night the next ten working days or something in that order - does that sound sensible?
KB22601 does seem to imply that I will only have to migrate the BESadmin and make some adjustments regarding policies on the 2010 server in order for the BES to support both an older Exchange as well as a new 2010 server - is this correct or have i misunderstood/missed something in this article?
If anyone has any experience with similar jobs and can provide me with input I will be very grateful 
lund wrote:Hi, we are in the process of migrating all of our users from an Exchange 2003 environment to a 2010 environment.
I have searching around the web and these forums and it seems as though I can have the BES server serve users on both Exchange server simultaneously - is that correct?
I'm hoping that is the case, the reason for this is that I have approx 120 BB users on my BES, migrating these will take some time and I really need users on both servers to have full mail support while performing this task.
My BES is on version 5.0.3.31.
What I'm hoping to do is to migrate batches of users each night for a couple of weeks, say 12 users per night the next ten working days or something in that order - does that sound sensible?
KB22601 does seem to imply that I will only have to migrate the BESadmin and make some adjustments regarding policies on the 2010 server in order for the BES to support both an older Exchange as well as a new 2010 server - is this correct or have i misunderstood/missed something in this article? That is correct.
If anyone has any experience with similar jobs and can provide me with input I will be very grateful
Follow that article but you dont have to move the users over right away, just BESAdmin account. Then once you know it works, start moveing users over.
Hello again, it seems as though I'm on the right track here
The BESAdmin has been migrated to the new Exchange 2010 cluster, and mailservices now work for users on both the old and new mail clusters.
I do however have an issue with calendar sync after moving my own mailbox to the new exchange environment.
I will look further into this but if anyone knows what it might be, please let me know.
I'm hoping a reactivation is uneccessary as it would be a true pain to assist all 120 users with this 
Conctact sync haven been tried yet - will do so soon and let you know
EDIT: Contact sync has been tried as well - not working good.
The status as of now:
Calendar appointments sync from PC to Phone, but not the other way.
Contacts don't sync Either Way.
I'm trying this on a 9900 with OS 5.0.0.540 - Outlook 2007 where the MBX is now moved to Exhcange 2010- BES version is 5.0.3.31.
Get-MailboxDatabase | Add-ADPermission -User "BESAdmin" -AccessRights ExtendedRight -ExtendedRights Receive-As, ms-Exch-Store-Admin
We have now started to migrate some users over to a new server. For my part it worked perfectly, but in other cases - mail dissappears from the BB inbox and in one instance a user can send mail from his BB but not recieve new mail on it.
So a few strange ussues but things are moving along without any major showstoppers - which is nice
