After migrating from Exchange 2007 to Exchange 2010, workstations running Outlook in cacheded mode were not getting latest version of the GAL. When manually trying to download offline address book within Outlook, it would just hang. From the EMC, I checked the name of the OAB (Org, Mailbox, Offline Address Book (tab)), and noticed it wasn’t named the default ‘Default Offline Address List’. In this case it was called ‘KTS Offline Address List’. Shame on us for trying to personalize… ha!
Anywho, renamed OAB to ‘Default Offline Address List’, did a right-click + update on the OAB… and then tried manually downloading the OAB from Outlook again and this time it took about 10 seconds. Outlook GAL was now up-to-date and even a post in my event log (app) ‘OAB Download Succeeded’.