Outgoing email blocked

I use Thunderbird email client. Following the latest Avast update I can not send email. The message is “smtp connection timed out”. By disabling the mail shield I am able to send email. How do I teach Avast to recognize the email?

Hi, you’re not the first who reported it. (https://forum.avast.com/index.php?topic=216766.0)
Do you get any error message…?

The error message mentioned in my initial post: “connection to outgoing server timed out, try again”
This happened following the last Avast update on 1 March. Disabling the shield allowed a test email to go out. I can also go toe ISP webmail page. Options like that should not be necessary!

I have discovered that, occasionally, SMTP server certificates go out of date or the server’s certificates are misconfigured. When that happens, AVAST might block the outgoing mail because the server is not properly trusted. If you are sure of your SMTP configuration in your email client, you can turn off AVAST’s outbound mail scanning. (Bring up the AVAST client by double clicking the AVAST icon in the Windows tray, and then from the Menu, select Settings ==> Protection ==> Core Shields ==> Mail Shield, and uncheck “Scan outbound mails (SMTP)”.)

Posting in a 2 year old thread isn’t really helpful.