Cannot send some email from locally hosted Exchange Server to comcast.net accounts

Hello, how are you? I hope your weekend has been a good one! I am sorry to hear about the email trouble while using your exchange server. Are you able to log into those email accounts from https://comca.st/30s7fpB? We want to make sure that email accounts or usernames are still active. 

I definitely can log in to the account. Both email addresses I mentioned are part of one personal home internet account with comcast (my account allows up to six email addresses). One is my primary personal email for the last 15 or 20 years. The second address I'm using for at least six years.

I've received email (not from  my business exchange server but from somewhere else) to one address 30 minutes ago, and to the other 1:30 hours ago.

Freddy

That's a good thing! That means those usernames are active. If you log into your Comcast account are you able to send an email to yourself (the email you are logged into) to test inbound and outbound emailing? We could also try sending to another email address and receiving from another email address. Such as a Gmail or Yahoo account you have access to. 

This was the first thing I've tried. But just to get it out of the way I've tried again. Sending email to this account from my personal comcast account works fine.

On the other hand when I send an email from the exchange server to my personal email it doesn't get there. After some hours I get back a message that my email is delayed and after another day or so the delivery failed.

Freddy

Thank you for taking the time to explain everything to us so we can get a better understanding of what's going on. I know how frustrating this is for you and you have reached the right team to help. Can you please send us a private message with your name, the full address, and the phone or account number?