We have had an ongoing problem for several months of our mail getting returned with an error message when only sending to certain Email addresses. The error reports:
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<technicpos.com #5.5.0 smtp;553 220.127.116.11 mail rejected due to excessive spam (Spamcop, SORBS)>
We have verified with almost every Blacklist that we ARE NOT LISTED in any database under our IP address or our Domain technicpos.com.
It also only seems to occur when sending to certain email addresses with domains at aol.com, yahoo.com, *.us etc.
We are completely baffled by this and are in need of resolving this as soon as possible. We have researched all of the known blacklists with our mail servers IP address of 18.104.22.168 and searching to see if our domain technicpos.com is listed either. All searches we perform come up clean and report that the IP address and domain are not listed in any database.
Somebody Please Help!