This article describes how to add UPN suffixes to a forest. Adding these suffixes gives you the ability to use a friendly user-logon name that does not match the domain's or parent domains' naming structure.
- Open Active Directory Domains and Trusts.
- Right-click Active Directory Domains and Trusts in the Tree window pane, and then click Properties.
- On the UPN Suffixes tab, type the new UPN suffix that you would like to add to the forrest.
- Click Add, and then click OK.
For additional information about UPNs and user logon names, click the article number below to view the article in the Microsoft Knowledge Base:
243280 Users Can Log in Using User Name or User Principal Name