Hi:
We have a server which is hosting several domains. Using this server we cannot send any email to any domain that is behind the email security product.
According to our logs, emails are correctly delivered:
maillog:Jan 25 10:15:26 XXXXXXXX postfix/smtp[10062]: EBC616620183: to=<XXXXXX@XXXXXX>, relay=cluster8.eu.messagelabs.com[XX.XX.XX.XX]:25, delay=1.6, delays=0.9/0/0.26/0.46, dsn=2.0.0, status=sent (250 ok 1485335726 qp 29326 server-13.tower-178.messagelabs.com!1485335726!82147396!1)
However, they are never delivered to the user inbox. Some users of the Email Security have told us that they got a warning that spam was being sent and could whitelist one of our domains. Normally, what happens is that emails are not delivered, recipients get get no warning at all and we get no error message in our server's logs so the message is simply lost without anyone noticing it.
I checked the symantec IP Reputation tool and this was the result:
The IP address XX.XX.XX.XX was found to have a negative reputation. Reasons for this assessment include:
- The host has been observed sending spam in a format that is similar to snow shoe spamming techniques.
We have checked several DNS black lists and the ip is not listed there. We have checked the ougoing email and we are not observing any abnormal email deliveries. Does anybody know why our reputation is negative? I tried to remove the IP using the reputation tool and it worked, but after a few hours it got a negative reputation again.
Hope anyone can help. Thanks in advance,
Alfonso