We have used limesurvey to send invitations and confirmations. It is not a seeding, we sent 400 emails to people who we knew their name, family name and email address. Email was personalized with "Dear Mr. [Name]".
Our IP was included in www.spamhaus.org and has been blocked. I am not sure if it is due to the phpmailer configuration. This is the message showed in www.spamhaus.org
"IP Address XX.XXX.XXX.XXX is listed in the CBL. It appears to be infected with a spam sending trojan, proxy or some other form of botnet.
It was last detected at 2013-XX-XX 02:00 GMT (+/- 30 minutes), approximately 6 hours ago.
This IP address is HELO'ing as "localhost.localdomain" which violates the relevant standards (specifically: RFC5321).
The CBL does not list for RFC violations per-se. This _particular_ behaviour, however, correlates strongly to spambot infections. In other words, out of thousands upon thousands of IP addresses HELO'ing this way, all but a handful are infected and spewing junk. Even if it isn't an infection, it's a misconfiguration that should be fixed, because many spam filtering mechanisms operate with the same rules, and it's best to fix it regardless of whether the CBL notices it or not."
Any idea to avoid this?
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