Go to Basic Configuration > User Directory to view all the registered email domains for a user account and add new domains.
Search the user directory to locate the user account(s) whose email domains you want to view. See Searching the User Directory.
From the search results header, click Get Email Domains.
The domain summary window displays showing all the registered domain(s) for the user(s) in your search results. Any domains that are not registered on your LDAP system appear in bold.
Click Add Unregistered Domains to add an unregistered domain. Check the domain(s) which you want to add to the user account and click Add Domains.