ActiveSync "migration" when migrating from Exchange 2007 to 2013: supported or no?

My customer is migrating from SBS 2008, and a large number of their staff use ActiveSync-enabled devices (iOS and Android) to access their Exchange 2007 mailboxes.  We plan to migrate them to Exchange 2013, and the mailbox store is small enough that a coexistence deployment shouldn't be necessary (in other words, we're going to move everyone's mailboxes more or less at once).

Will ActiveSync devices gracefully/seamlessly reconnect to user mailboxes on the new server, like Outlook does?  Or will we need each and every user to redo their ActiveSync profiles on their devices?
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

Will SzymkowskiSenior Solution ArchitectCommented:
As long as you have your virtual directories setup properly on your Exchange 2013 server you should not have any issues when the mailboxes are moved to Exchange 2013 from 2007.

Depends... if autodiscover is working properly and you leave the old server in-place for long enough that the mobile devices get the new server settings, you should be fine.

There's a good chance the hostnames probably won't change, so the mobile devices won't even realize that a new server has started serving them. They will still connect to for the autodiscover settings, and then to or whatever you have the external hostname set to for the actual mailbox access.

In practice... IMHO it's tricky to do it right. The first time I did this all the iPhones switched over fine, and all the Androids and blackberries crapped themselves as soon as we took down the old server, requiring us to remove and re-add the accounts on everyone's phones. I probably did something wrong, but it wasn't immediately obvious to me what it was and in the end it was faster to walk around to each cubicle and talk to the 15-20 people who needed it than it was to try and solve it on the server side.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
AA-in-CAAuthor Commented:
Thanks, Will and Frosty!  

Frosty, Autodiscover is where it gets tricky.  The prior admin never configured it properly/fully, so whenever existing staff buy new phones, or a new hire comes in, a tech has to manually 'point' the phone at the external address for mailbox access, Mail.OurDomain.Org.  Once the phone/tablet is pointed at Mail.OurDomain.Org, setting up the user's mailbox access proceeds normally,  

If I'm not mistaken, resolving this issue is as simple as creating a CNAME record with our external DNS provider, pointing Autodiscover.OurDomain.Org to Mail.OurDomain.Org.  Is that your understanding as well?
Simplify Active Directory Administration

Administration of Active Directory does not have to be hard.  Too often what should be a simple task is made more difficult than it needs to be.The solution?  Hyena from SystemTools Software.  With ease-of-use as well as powerful importing and bulk updating capabilities.

Will SzymkowskiSenior Solution ArchitectCommented:
If you are manually pointing to your external OWA address for ActiveSync then everything will need to be manually re-configured.

If I'm not mistaken, resolving this issue is as simple as creating a CNAME record with our external DNS provider, pointing Autodiscover.OurDomain.Org to Mail.OurDomain.Org.  Is that your understanding as well?

Yes you need to create a cname for this entry in your certificate (UCC). If this DNS name is not in your cert then you need to congiue SRV records on your external DNS.

You also need to configure the
set-ClientAccessServer -AutodiscoverServiceInternalUri

Open in new window

as well. Even with autodiscover configured correctly, all of the phones are still manually set to point to a different URL on the phone rather than using autodiscover so that is something else that you need to consider as well. Your best bet would to actually test this in your environment with a couple of users to determine exactly how your users will be affected.

Vincent BurtonCommented:
Introducing Exchange 2013 into an Exchange 2007 environment can be a challenging task.  One of the most overlooked, and least documented topics I see is the proper configuration of URLs for Proxy and Redirection:

You may also take help from this informative blog post - Step-by-Step Exchange 2007 to 2013 Migration:

Hope it helps you!
AA-in-CAAuthor Commented:
Thank you, Will and Vincent, that's incredibly helpful.  

MS Partner support has been telling me that they "recommend" redoing the ActiveSync device profiles for users whose mailboxes get migrated to the new server.  They're not giving me a lot of detail as to why, just that it can be problematic.  We can redo them, but it'd be physically impossible to redo profiles on 75 iPads/iPhones/Androids all at once without inconveniencing our users (we don't have an MDM platform to help us with this).  Which leads to my next question, about simply sidestepping that issue by doing a phased migration with 2007/2013 coexistence...

In a coexistence scenario, where Exchange 2013 proxies requests for mailboxes living on the 2007 server to that server, will ActiveSync still behave normally for users still on the old server?  In other words, if user John has his mailbox moved to 2013, we need to redo his ActiveSync profile.  But if user Anna has her mailbox on the 2007 server, we don't need to redo hers yet, correct?  If that's the case, we can migrate batches of 5-10 mailboxes at a time, and schedule the corresponding users to give us their smartphones/tablets for reconfiguration, in an orderly way.
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.