10-12-2010 06:59:52 AM
Along with the other problem I mentioned with bellsouth email accounts. Our company also has other offices with ATT business class dsl which have sbcglobal email accounts. For about a week now those locations are having problems sending emails which have pdf attachments. They appear to be triggering the yahoo spamcop spam filter. The error message which bounces back to the sender is "Remote host said: 550 Unable to add (users email address) because host 188.8.131.52 is listed on RBL bl.spamcop.net."
A whois search reveals that ip address is owned by yahoo. Therefore it appears the spamcop program used by yahoo is actually blocking itself when pdf attachments are sent in an email by an sbcglobal email account.
Solved! Go to Solution.
10-12-2010 09:54:51 AM
10-13-2010 02:38:14 PM
The problem isn't that AT&T is blocking the mail but that the AT&T mail server is in the SpamCop database. The recipient's mail server is rejecting the incoming mail because it is *originating* at a blacklisted AT&T server.
I've been having this problem intermittently for the last few weeks, probably because my outgoing mail isn't always routed via the blacklisted server.
For example, see this SpamCop report http://www.spamcop.net/w3m?action=blcheck&ip=98.13
AT&T needs to find the source of the spam and cut it off to keep their servers from getting added to the black list.
05-01-2012 05:38:58 PM
I would like to thank everyone for taking the time to post your comments and opinions related to this topic. This topic has been thoroughly discussed and will now be closed, as it is very old. If you still have questions please start a new topic, so the information is up to date.