Global address list cached mode not updating
In addition to this there a a few methods by which your Outlook clients get the offline address book.*Note: Unless you are NOT in cached mode.
Even removing the OAB files from the client and having it re-download does not seem to work all the time. Forced an address book update on the Server side, waited for a day to even let the automatic update run, everything says it has run successfully.
First off our environment is an Exchange 2010 SP1 environment.
It was updated from an Exchange 2003 environment, and it is my assumption that when that conversion occurred the public folders etc...
Exchange 2013 only supports Outlook 2007 (post SP3 and cumulative update), and Outlook 2010 must be at SP1 with cumulative update. For public folder distribution ensure the public folder database is mounted, and at least one server holds a replica.
Also in the properties of the mailbox database, your users are using, make sure it points to the correct public folder database.