How do I change my default Outlook address book?

If you'd like Outlook to default to showing you your "Contacts" list instead of the Global Address List or other Address Book List, here's how:

1. In Outlook, navigate to your Home ribbon and click Address Book:
   
2. Click Tools > Options
   
3. Now you can choose "Start with contact folders" or choose a Custom option:
   

Once you click OK, you'll see that when you click To: in a new email, or open your address book, it will show you your Contacts or custom folder first.