My home server is on comcast internet so I'm successfully using the comcast smarthost to relay my email out to the web. However, all the emails I send back to the box bounce back to me as shown below and I can't find any clues in the logs.
Delivery of a message from you has exceeded the retry time: From: email@example.com Subject: RE: not working The following recipients could not be delivered: firstname.lastname@example.org
I'm using a domain registration site to point myhost.ca at my IP address and I think I've got my MX record set correctly.
This site http://mxtoolbox.com/SuperTool.aspx says the following about my MX record.
Pref Hostname IP Address TTL
30 myhost.ca XX.XX.XXX.XXX 60 min
I've configured my router to forward the following ports to my ubuntu server:
FYI the webserver and ssh access both work fine. Incoming email seems to be the only thing that isn't working.
From the local machine I can telnet to port 25 and 587 and "HELO myhost.ca" responds as expected. From any machine outside my house telnet won't connect to those ports and times out. I expect port 25 is blocked by comcast but I'm expecting 587 to be useable.
Can anyone suggest next steps for debugging?
thanks for reading!