Delivering to Comcast?

[BGSWebDesign]

Hi,

I've not had problems in the past, but just recently I got this reply from a Comcast Email address:

Code: [Select]


Connected to 204.127.225.26 but sender was rejected.
Remote host said: 521-EHLO/HELO from sender 4.78.168.28 does not map to mail.trueswitch.com in DNS
521-sending machine name must be provided as a fully
521-qualified domain via EHLO/HELO command.
521-see section 4.1.1.1 and 4.1.4 of RFC 2821
521 521: Please see http://www.comcast.net/help/faq/index.jsp?faq=SecurityMail_Policy18784 for more information


Here is the link suggested to look at in the Comcast Faq:
http://www.comcast.net/help/faq/index.jsp?faq=SecurityMail_Policy18784

And, here's a quote from that page:

mail server does not properly identify itself

Ok, has anyone else had this, is there some way to correct this in LMP so that the Mail Server can properly identify itself?  Dean?

[DW]

Hi Brett,

I checked out the recommended RFC and did some thinking on this.  It could be a server configuration issue at your web host.  My reasoning is as follows:

ListMail -does- say EHLO but this is when queuing, which is separate from the final delivery connection and communication.  I believe the SMTP server software's EHLO to the remote server during final delivery is the issue.  They may be sending the wrong domain name, or a reverse IP entry may be required. (Are your emails sending from the same IP as they were?)

You mentioned you have not had this problem in the past.  It might be temporary - if it affected the entire system your host probably would have caught it quickly by way of complaints.

Please let me know if I can be of further assistance with this.  Unfortunately my ability to test is limited by not having administrator access to the server.

Regards