Welcome to Comcast Help & Support Forums
Find solutions, share knowledge, and get answers from customers and experts

New to the Community? Start here.




online now




Sending non-comcast email through comcast smtp servers

Frequent Visitor

Sending non-comcast email through comcast smtp servers

This is technical, and I'm very well versed in this technology - please don't reply with the equivalent of "is the cable plugged in?" Sorry to be snarky, but I'm looking for a solution to a a problem I'm seeing, not a RTFM response.


I have several domains and dozens of email addresses. I redirect a lot of those addresses to a couple of comcast addresses to leverage the spam filtering and secure IMAP. I would like to be able to send outgoing mail through comcast's SMTP servers because of their connectivity and reliability, but now I have trouble doing so.


I don't actually send ANY email with a from address matching my comcast accounts - comcast is my ISP only, ALL of my email comes from and goes to non-comcast addresses.


Until recently (sorry, no more concrete definition, probably a month or two), I had my email clients on various platforms set up to send outbound mail via comcast's SMTP servers using TLS (SSL), authenticated with my comcast credentials. At some point in the not-too-distant past, this stopped working, and emails with a "from" address that didn't match the comcast account simply didn't get sent - no errors, no bounce, just didn't happen.


My question is twofold: first, what, if anything, can I do to get emails to go through with non-comcast "from" addresses and second (if there is), is there a way I can flag domains as legitimate users of the account?


I'd like to avoid having to manually sync every email address (as I mentioned, I have dozens of addresses), and would really like to be able to say "any sending address from domain <whatever>.tld is ok through this account"


Thanks in advance for any constructive replies.