>From where do they get that bounce message? From a host internal to your >network or from hosts out on the Internet?
The bounce message is only when they send certain domains that are external to our network. > >If that's coming from an internal MTA, I'd suggest that MTA doesn't >believe your Exchange server is a legitimate source for mail from your >domain. If that's coming from external MTA(s) then others on the public >Internet apparently don't believe your public IP address is a legitimate >source for mail from your domain. Do you publish SPF information or use >Domainkeys? Has your public MTA's internet IP address changed recently? AFAIK we arent using Domainkeys, we use DynDNS.com and a check on our SPF records gives "The TXT records found for your domain are: v=spf1 ip4:202.44.190.48/28 ~all SPF records should also be published in DNS as type SPF records. No type SPF records found. Checking to see if there is a valid SPF record. Found v=spf1 record for afnsecurity.com: v=spf1 ip4:202.44.190.48/28 ~all " the external IP of the exchange server is 202.44.190.49.. could this be the cause? If so why would only certain domains be giving the error? Regards, Jon -- View this message in context: http://old.nabble.com/Bad-Helo-Host-impersonating-tp31214638p31216483.html Sent from the SpamAssassin - Users mailing list archive at Nabble.com.
