Updating global address book
On the toolbar, in the farthest group on the right labeled "Find", click on "Address Book" 2.In that address list, select "Tools" and then click on "Options" 3.In the drop down menu underneath where it says "When opening this address book, show this address list first:", select "Global Address List" or whichever option you would like the new default to be.Outlook Web Access provides a useful set of tools for your business, including the Global Address Book for storing all of your contact information in one convenient location.If these attributes are present, then the AD Objects that are Mail-Enabled or Mailbox-Enabled will appear in the GAL – and ultimately the Offline Address Book.You can see the list of attributes that will be put into the GAL using When Outlook users are running in cached mode, they rely on the Offline Address Book (OAB) to provide them with access to one or more addresses (that are always available when they are connected directly to Exchange) The OAB is rebuilt and downloaded on a default schedule as shown below.
Check out this knowledge base article I found in the Broward College knowledge base.
Here is a quick way to copy the GAL to your persona contact list and therefore have everyone in your contact list.
This document seeks to address and clarify the small misunderstanding surrounding the GAL (Global Address List) and the OAB (Offline Address Book).
Because of this, a new user may not be visible in the address book, or changes to a user’s name, address, etc.
may not be available even though such changes have been made in Active Directory.