seriously... what a tacky product. I never respond to their challenge emails. I consider them spam. I also ignore any email from the person about not getting email, then complain about it. They chose to not get email.

Good thing it is not working or this response would not get to you. Perhaps you have already downgraded and this reply will not get to your inbox while your spam tool mindlessly replies to a do not reply email address.

My guess is your mail providers settings for ports, encryption etc really do not match those of spamassasin. They offer no advice on what settings should be used, making it "simple" for the user.

a test of the server using guess work suggests the server does not support TLS encryption of connections above V1. So I suggest you look at your server settings and change any connection security to none and set the port to 143 if using IMAP or 110 if using POP. Got a concern about not using encryption. Talk to spamassasin about updating the TLS version they support. While I can not locate the bug involved, I would assume TLS v1.0 support has been removed to comply with the credit cards industry standards.

For some background you might want to read this https://www.comodo.com/e-commerce/ssl-certificates/tls-1-deprecation.php

I never heard of SpamAssassin, I use Spamarrest. I am happy with it. I did get your message by checking the unverified folder. Saves me hours a month by trapping spam. No skin off my a** whether you care for it or not. But thanks for the useful parts of your response. :)

Anyway, I will check the settings based on your suggestions, but at this point, I will likely just stick with v37 of T-bird. When I have time, I may just upgrade one major version at a time until it stops working and roll back if needed.

Thanks, Matt