How To Block user to send email locally or externally In zimbra

Step 1: Open file /opt/zimbra/conf/zmconfigd/smtpd_sender_restrictions.cf and add the below line at the top. check_sender_access lmdb:/opt/zimbra/postfix/conf/restricted_senders Step 2: Open file /opt/zimbra/conf/zmconfigd.cf and add below lines before "RESTART mta". POSTCONF smtpd_restriction_classes local_only POSTCONF local_only FILE postfix_check_recipient_access.cf…