I have Postfix and Dovecot installed and running on the VPS. Using telnet once from VPS, and once from a client machine, I'm composing exactly the same messages. Everything is working but when sending from the client, the email goes to Gmail's spam.
telnet mydomain.com 587
Only one thing from the mail.log is different from when I send it from the VPS, the message-id is empty:
Aug 26 13:13:37 server postfix/smtpd[32197]: connect from 1-2-3-4.my.domain.com[1.2.3.4]
Aug 26 13:14:06 server postfix/smtpd[32197]: D762C582448: client=1-2-3-4.my.domain.com[1.2.3.4], sasl_method=plain, sasl_username=user@example.com
Aug 26 13:14:14 server postfix/cleanup[32211]: D762C582448: **message-id=<>**
Aug 26 13:14:14 server postfix/qmgr[32195]: D762C582448: from=<user@example.com>, size=300, nrcpt=1 (queue active)
Aug 26 13:14:15 server postfix/smtp[32213]: D762C582448: to=<example_user@gmail.com>, relay=gmail-smtp-in.l.google.com[74.125.53.27]:25, delay=11, delays=9.9/0.07/0.55/0.69, dsn=2.0.0, status=sent (250 2.0.0 OK 1314353655 k7si869205pbk.67)
Aug 26 13:14:15 server postfix/qmgr[32195]: D762C582448: removed
Do you have any ideas? Thanks.