UACES Facebook O365 - GAL vs Offline GAL - Outlook

Choosing the Right GAL for Your Address Book

The Global Address List (GAL) is the central repository of contacts. 

Changes to the GAL are immediately available if you are using Outlook Web Access (OWA). However, on a regular Outlook client, a change might not appear for up to 24 hours. This difference is because the default configuration for an Outlook client is to use something called Cached Exchange Mode. In Cached Exchange Mode, the default is to use the “Offline Global Address List” (OAB).

Normally, the Offline Global Address List is preferred because it is more responsive than the online version. You can make the Online Global Address Book your default but this isn’t recommended for slow network connections.


  1. Click the Address Book button. The button is located in the Find group on the far-right of any Home ribbon. 
    Address Book
  2. In the Address Book, click on the Tools menu and select Options
    Tools Menu
  3. The Addressing dialog box offers three radio button choices for your list order. The default selection is Start with Global Address List. The problem is which Global Address List.  We need to add Global Address List to the Custom list. 
    Addressing dialog
  4. Click the Add...button and use the Add Address List selector to include Global Address List as a custom item.
  5. Close the Add Address List dialog.
  6. Near the bottom of the Addressing dialog is a selector labeled When opening the address book show this address list first: The default here is Choose automatically.
  7. To override the automatic selection, pull down the arrow and select Global Address List.
  8. At this point, it's not essential that you have the Custom list selected.  It's up to you as to which address list you want to check first.
  9. Click OK to exit the Addressing dialog.