and did you contact comcast support because you clearly think this is "in error"?

I checked the IP address given. 37.19.210.10 It appears to belong to an VPN service provider. I suggest you have a meaningful conversation with Comcast about sending email from non Comcast IP addressed ( including VPN ones) they have never allowed it in my decade with this forum. Turn off the VPN and your problem will most likely go away.

Matt,

Thanks so much for the quick reply and suggestions. Your were correct that it was a VPN issue. I use the Mozilla VPN and when I turned it off and restarted the computer, I was able to send messages again. So thank you.....

Bob Rusnak

It is possible the VPN has some sort of exceptions for some ports or applications.

Personally I really have no real use for a vpn. I have little interest in viewing geoblocked content. Most of the web sites I visit, Google, eBay, Facebook, LinkedIn even this one already know where I live and work and are more likely to want to block me than accept I have suddenly moved to Estonia.

Then there is the issue that your credit card looks to be used from odd locations when you use the VPN when making purchased from web sites you have given your physical address to to make deliveries. Your credit provider then either puts you on a watch list of just blocks the transaction because they also know you used your card in the supermarket down the road 20 minutes ago and then purchased fuel for your car at the service station around the corner, so you can not be in Guangzhou now buying new bed linen.