Apr 15 14:02:25 server.tld postfix/local[67533]: D8C46C9014D: to=, relay=local, delay=1956, delays=1936/0.01/0/20, dsn=4.2.0, status=deferred (cannot update mailbox /var/spool/mail/user for user user. unable to create lock file /var/spool/mail/user.lock: File exists)