Because of this, a new user may not be visible in the address book, or changes to a user’s name, address, etc.The default configuration for Exchange 2010 has the Address Book will update every 24 hours at 5am.By using the Offline Address Book, Outlook does not have to connect to Exchange in order to resolve names or open the records for each user.This reduces network traffic and improves performance.This feature requires you to use a Microsoft Exchange Server 2000, Exchange Server 2003, or Exchange Server 2007 account.
The easiest way to do this is simply connect to Outlook Web Access, and query the GAL directly (OWA uses the GAL no the OAB like Outlook running in cached mode does). The User/Mailbox IS listed on the Server But NOT in Outlook.
To resolve this you have two option, manually update the Address Book or customize the update schedule.
After completing this tutorial you will have configured Microsoft Outlook to always reference the latest version of the global address book directly from the email server rather than referencing a downloaded local copy. After following these steps, you will only be able to access the global address book while Outlook is connected to the server.
*** NOTE: The GAL is essentially a real-time / online representation of AD Objects that are Mail Enabled for Microsoft Exchange *** The GAL contains information for all email enabled users, Distribution Groups, and Shared Mailboxes and Exchange Resource Mailboxes.
GAL Objects are directly viewable in the Exchange Management Console/Shell and OWA and Microsoft Outlook BUT ONLY IN ONLINE MODE – The GAL will only present objects that have AD Attributes beginning with ms EXCH* (and some others) populated that it uses to filter on.