To search contacts by last name in the Global Address List in Outlook, please do as follows:

1. Click Home > Address Book to open the Address Book.

Note: You can also open the Address Book by clicking the To, Cc, or Bcc button in a composing email.

Address Book dialog box, please select the Global Address List from the Address Book drop down list, and click Advanced Find. See screenshot:

3. In the popping out Find dialog box, please enter the last name you will search by into the Last name box, and click the OK button. See screenshot:

Now you will see the contact with the specified last name has been found out in the Global Address List. See screenshot:

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