Avast blocking incoming & outgoing email pop3/imap/ smtp

[Geolane]

Email using Windows Live Mail and Thunderbird are blocked.  I can't send or receive.  If I turn off Avast, the email works for both.  How do I allow email to work without compromising Avast's scanning of incoming threats?

23.4.6062 (build 23.4.8118.783)

[rocksteady]

Do you have Avast Free or Paid?
If you are using Avast Firewall, is it set to PRIVATE not PUBLIC?

[Geolane]

The free version.  I am using Windows 10's firewall.  I suspect I need to white list the mail server, but I'm not sure how to do that.

[rocksteady]

I wonder if this may help: https://support.avast.com/en-ww/article/91/#pc

[Geolane]

Thank you for the link to the Avast support section.  I get as far as exporting the Mail Shield certificate.  When I try to import it into Thunderbird, I get a box that says "This certificate is already installed as a certificate authority."  That suggests to me that this is not the cause of all email being blocked.

Another thing that has not worked is going to the Avast shields Mail section and unchecking the boxes to Enable Mail Shield, Scan Inbound Emails, and Scan Outbound Emails. 

The only thing that has worked is to temporarily turn off all of Avast's shields for 10 minutes when I want to check or send email.  That's how I know that Avast is causing this.

[Geolane]

Add another thing that didn't work - disabling IPv6 as a communications protocol as seen in the discussion here:

https://forum.avast.com/index.php?topic=319789.0

The problem continues.  The only way to send or receive email is to stop the shields.

[RedFan]

I had the same issue , also with avast one and free AV past week .... uninstalled everything.

[Geolane]

Did you reinstall Avast or switch to another antivirus program?

[RedFan]

Switched back to Bitdefender.

[Geolane]

Well, today email is working again even in the presence of Avast.  Yesterday I had uninstalled Avast using Revo Uninstaller and then reinstalled Avast fresh.  After the reinstallation, email was still being blocked from connecting to the server.  Today email is working.  Avast installed its secure browser, which I didn't want and I uninstalled that yesterday.  I don't know if that had any effect on today's performance.

[rocksteady]

If uninstalling Avast, it is best to use their own avastclear program, which can be downloaded here: https://www.avast.com/uninstall-utility#pc

That should do a full removal for a clean re-installation of Avast.