Topic: Mix of SMTP issues...
I'm still facing some problems with my SMTP.
If I used local SMTP set up with iRedMail I have problems with some domains. Some domains don't receive my mails even if there are no errors in the logfile.
Other domains answer something like this:
relay=mail.register.it[220.127.116.11]:25, delay=5.4, delays=0.02/0.02/5.4/0, dsn=4.4.2, status=deferred (lost connection with mail.register.it[18.104.22.168] while performing the HELO handshake)
If I use relayhost option in main.cf my ISP's SMTP considers most of my outgoing mail as SPAM:
<email@example.com>: host free.dsl.vodafone.it[22.214.171.124] said: 554 5.7.1 Message refused by DeepHeader check. This email has been rejected. The email message was detected as spam. (in reply to end of DATA command)
At now I'm not able to get my SMTP working. And I'm not able to understand why my ISP's SMTP reject only some mail from my server, yet.