Port 25

@XfinityJeniece​ It is good to know that you are proficient at repeating the company line. Blocking port 25 due to the risk of potential abuse is kind of like blocking email because it is prone to phishing. I suspect that the policy is due to some other reason (perhaps Xfinity just doesn't want its customers operating mail servers) and the current policy is a cover up. In any case, it is impossible to operate a mail server without access to port 25. I have been operating a mail server for over 15 years. I know what I am doing. I will not set up an open relay. I probably won't even allow outgoing email. We know that it is possible to open port 25. The intent of my question was simply to find out what hoops I would have to jump through to get the port opened If worst comes to worst, I'm under no contract with Xfinty so I could presumably easily switch to a different internet provider. For now, I will simply contact the Customer Security Assurance team a few times each day until they get tired of hearing from me.

@user_365779​ Or just pay a port redirect service $12/year, make them your primary MX and they'll sing mail to whatever port you want that isn't blocked.  Submit on 587, and you also won't run into that problem were the rest of us are all blocking all the ISP's consumer dhcp pools and rejecting your mail as spam.

Your mail will also queue up at the redirect when your IP address changes , so you won't loose anything while you fix your redirect IP address when that happens.

Great suggestion. Currently I have Namecheap forwarding email from my registered domain, but I didn't see any suggestion that they do port forwarding as well. Can you suggest the names of companies that do port forwarding?

@user_365779​  Used dynu (dot) com in the past.  They're legit.  Just get a $25 prepaid visa card if you don't trust online folks, or don't want it tied to anything you have financially, and you're good to go.  I've moved on to just leasing rack space these days at decent hosting company with good reputation IP blocks in a bigger setup.

As far as the TOS goes and acceptable use policy, if you are running email hosting for yourself, that's fine.  Running email hosting for others, that's not.  A redirect service is the same thing as checking your email on another email provider.  You are authorized to send mail using Xfinity's email servers, and it is also acceptable to send email using some other email provider.