Exchange 2010 offline address book does not update

In Exchange 2010 it takes even longer to synchronize the changes in the OAB than Exchange 2007. After the OAB is updated, which by default is once a day, it may take up to 8hrs for the OAB to be available to the client. The reason is that the OAB is generated in the MAILBOX role and needs to be copied to the CLIENT ACCESS role. The CLIENT ACCESS role checks for changes every 8 hrs. On top of these delays, if a client does not close/open his or her Outlook, it can take even longer for a change to take place.

Take a look at my blog post to resolve the issue. http://www.jasoncoltrin.com/?p=77

Also you can read up on how the OAB is distributed and the scheduling of that distribution here: http://www.jasoncoltrin.com/?p=312

It's the Exchange CAS not updating the Offline address book file:

C:\Program Files\Microsoft\Exchange Server\V14\ClientAccess\OAB\Something-Something-Darkside\oab.xml

I just restarted the Microsoft Exchange File Distribution service on the CAS server and it updated.

Then force outlook clients to update the OAB.