Sonicwall TZ215 anti-spam


I'm trying to figure out why I cannot send to gmail addresses when the ANTI-SPAM service on my firewall is turned on.

When I have it enabled I get bounce back messages from google.  When I turn it off the emails flow properly.
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btanConnect With a Mentor Exec ConsultantCommented:
Anti-spam hook to port 25 SMTP and if you experience the below then likely need to have custom port
(ref EE -
e.g. telnet 25 (FROM THE OUTSIDE) responds with ESMTP Sonicwall.
e.g. telnet 25 (FROM THE INSIDE) gets a response from the Exchange server (as example of mail server)

also I am thinking if the sender is having a private address hence not allowed to send back or the public IP is blacklisted in blacklisted or not found in MX records in the email server connected ...
(ref -

Probably good to try other ext (not int) email accounts other than gmail such as hotmail or yahoo.. to see if it recurred..

Adding on another case is when mail server has enabled open relay which can allow spammers to abuse the use of your server to send spam without being an authenticated user. By default Sonicwall anti-spam will block any outgoing or incoming email to any servers with this option enabled. Use this website to check your email server:

May be good to start support check as well concurrently

Additional ref
Configuring anti spam

How to activate and configure Anti-Spam feature in SonicWALL UTM appliances

How to Open SMTP, IMAP or POP3 traffic to an Email Server behind the SonicWALL (SonicOS Enhanced)
mcioffi209Author Commented:
Discussed this with Sonicwall support and it was due to a rule in the firewall.

I made that change and we are working properly now.

All this was good info, but not the problem.
mcioffi209Author Commented:
While not the actual solution it lead me in the proper direction to get the issue solved with the techsupport folks.
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