I configured Dovecot on our mail server under Centos 5.3 (I think) some while ago now (about 2 years) and, to the best of my knowledge,it had been working correctly all that time.
However, one of the team wanted to use webmail while away from base and found that, although he could receive emails OK, he was unable to reply or send fresh emails. When he pressed Send he got a message “Authentication failed" in a pop-up box. He assured me that sending mail had been working and I was certain that I had tested that aspect when I was setting Dovecot up, at least for local mail. I tried to send email from my Dovecot account and had the same problem. Our MTA is sendmail and that is not configured to authenticate on outgoing mail, The configuration for sendmail hasn’t changed at least since the last update in 16 March 2015 (sendmail 8.13.8-10.el5_11). Dovecot uses php-5.5.5 in this set up. The relevant entry in /var/log/maillog when I attempt to send an email from Dovecot is: May 5 16:34:29 firewall dovecot: auth: Debug: auth client connected (pid=13001) May 5 16:34:29 firewall dovecot: auth: Debug: client in: AUTH 1 PLAIN service=imap secured lip=127.0.0.1 rip=127.0.0.1 lport=143 rport=51861 resp=AGNocmlzADB1dFkwdUcwNDkh May 5 16:34:29 firewall dovecot: auth: Debug: pam(chris,127.0.0.1): lookup service=dovecot May 5 16:34:29 firewall dovecot: auth: Debug: pam(chris,127.0.0.1): #1/1 style=1 msg=Password: May 5 16:34:29 firewall dovecot: auth: Debug: client out: OK 1 user=chris May 5 16:34:29 firewall dovecot: auth: Debug: master in: REQUEST 2607546369 13001 1 0bcf2e3a108cd9cd18eaff4b7de9c428 May 5 16:34:29 firewall dovecot: auth: Debug: passwd(chris,127.0.0.1): lookup May 5 16:34:29 firewall dovecot: auth: Debug: master out: USER 2607546369 chris system_groups_user=chris uid=514 gid=100 home=/home/chris May 5 16:34:29 firewall dovecot: imap-login: Login: user=<chris>, method=PLAIN, rip=127.0.0.1, lip=127.0.0.1, mpid=13002, secured May 5 16:34:29 firewall dovecot: imap(chris): Disconnected: Logged out bytes=11/334 May 5 16:34:29 firewall sendmail[13003]: u45FYTtd013003: localhost.localdomain [127.0.0.1] did not issue MAIL/EXPN/VRFY/ETRN during connection to MTA The webmail server and our mail server are the same system. The firewall is open for port 143. It is only send from Dovecot that fails authentication, all other outgoing mail is sent correctly. Does anyone have any idea where else I can look for clues as to why there is this behaviour? Suplementary question: what does the “Sign me” check box on the webmail log in page do? Many thanks. Chris
