Exchange 2010 Offline Address Book not refreshing

Offline Address Book on MS Exchange 2010

Another headbutter of a silly issue, but this one was quickly resolved.

We have Exchange 2010, migrated from an Exchange 2003 server that is still registered on he AD because I haven't gotten round to decommissioning it yet. I suspect the prescence of the EX2003 is an cause of the issue, even though I have moved the OAB to EX2010. Anyhow...



If we make a change to the Exchange environment, say add a user, they are added to the OAB but the changes are not updated on users PC's

My first thought was that it was a caching issue so I disabled caching and sure enough, the correct OAB is shown, re-enable caching and it reverts to the wrong one.

So simple solution; close Outlook, delete the cached OAB files (typically for Outlook 2003/2007 they will be in %localappdata%\microsoft\outlook and will have an .oab extension - if you're nervy then move them to a backup location)

Oh, BTY, in Outlook 2010 they are in %localappdata%\microsoft\outlook\Offline Address Book\CLSID and if you are connected to more than one exchange server, a different CLSID per server. Easy way to find out which one you want to delete/backup - open the utmplts.oab or udetails.oab in notepad and look at the name of the server and Exchange Administrative Group its reading from.

So, you've deleted or moved the .oab files - open outlook and F9 - voila - the correct OAB cached until next time you make a change!

Oh Yeah - this is for when DOWNLOAD OFFLINE ADDRESS BOOK doesn't work!