Hey! Recently upgraded to cyrus from cvs (2.1.0pre), it shown a great improvement in lmtpd, however, now I _sometimes randomly_ get the following: >>> DATA <<< 550 4.3.0 System I/O error. 550 5.1.1 [EMAIL PROTECTED] User unknown <<< 503 5.5.1 No recipients In sendmail log file it also shows User unknown error. Sometimes mail goes to [EMAIL PROTECTED] well... Ideas? Nick Ustinov Enterprise Solutions Group Director Vide Infra Grupa SIA 40 Brivibas St, Riga, Latvia, LV 1050 phone: +371 7812294 fax: +371 7812297 http://www.videinfra.com