Unable To Find Person In Address Book
Summary
If you're unable to find a person in the Address Book, it could mean that an email doesn't exist or the setting in your Outlook has changed to Offline Address Book (OAB). A scenario could be a new hire is onboarded and you're searching for this new person, but unable to find the person. If you're Outlook is in OAB then it didn't have a chance to sync to update the OAB.
Instructions
1. Navigate to the Address Book and click.
2. Click the drop-down and select Global Address List. This will sync with the server updating all the emails. You should be able to find the person.
3. If you find yourself stuck on the Offline Address Book or another list, it's most likely a setting. Go to menu bar of the Address Book and select Tools then Options. It will bring this setting. Choose Global Address List.