Dear all,
since a few days ago I am having a very strange problem with my roundcubemail. I have my own mail server (linux, postfix, dovecot, saslauthd). The mail server is for a part of a bigger company. Its SPF record is placed at the level of the whole company and is correct. Mail clients access the server via imap port 993 and smpt port 587 of my server. Local users can send mails from various clients like thunderbird through these to any address. Mails from roundcubemail are also sent correctly to any address except gmail. A message to any gmail address is bounced with the error message
" gmail-smtp-in.l.google.com[64.233.165.26] said:
550-5.7.1 [xxx.xxx.xxx.xxx 12] Our system has detected that this message
is 550-5.7.1 likely unsolicited mail. To reduce the amount of spam sent to
Gmail, 550-5.7.1 this message has been blocked. Please visit 550-5.7.1
https://support.google.com/mail/?p=UnsolicitedMessageError 550 5.7.1 for
more information. "
Their link contains just a general info about why my message could be spam. However, it is definitely not spam as the same message sent from the same local address to the same gmail address via e.g. thunderbird, is delivered without any problems.
I configured both the mail server and roundcubemail many months ago and have not changed the configs since then. The problem surfaced a few days ago.
Clearly the problem is with roundcubemail but I have no idea where to look. The imap and smtp settings in config.inc.php are
$config['imap_host'] = 'ssl://myhost.companydomain.com:993';
$config['smtp_host'] = 'tls://myhost.companydomain.com:587';
where myhost is the name of my computer hosting my mailserver.
roundcubemail version is 1.6.1
I would be glad to provide any additional info. Any advice?
Thanks in advance.