Postfix is rejecting emails with "Sender address rejected: not owned by user" error message.

Issue

• Is it possible to use username in the Outlook instead of email ID?

• The parameter  smtpd_sender_login_maps which looks up the LDAP database and in  smtpd_sender_restrictions, reject_sender_login_mismatch is supplied.  If Outlook is configured to use the user name as 'userid' then email is bounced back with following error in logs

   postfix/smtpd[3535]: > hostname [ip-addr]: 553 5.7.1 <email@example>: Sender address rejected: not owned by user email@example.com