Problems troubleshooting Thunderbird & Mail Shield

Avast Free Antivirus / Premium Security
1

I have a few problems following https://support.avast.com/en-ww/article/Troubleshoot-invalid-email-certificate .

When i try to import the exported certificate from Avast into Thunderbird, i get a notification, that this entry already exists. I manually deleted all of the Avast Section certs and tried to import it again, but still it’s alread imported.

Thus, i can’t receive my mails, because i’m always asked to add a security exception, which won’t work.

How to solve this Mail Shield-Mess?

2

What versions of Avast and Thunderbird are you using?

3

Both most recent version.

4

So can you confirm precisely :

Avast 19.1.2360 (free or paid, BTW?)
and Thunderbird 60.4.0 32-bit?

5

19.1.2360 yep
60.4.0 32 Bit yep.

And it’s the Free version

6

Please try the following steps in order (ensure you have a copy of the exported Avast certificate):

  1. Close Thunderbird and ensure it is fully shut down (no Thunderbird entries in Task Manager)

  2. Temporarily suspend Avast Mail Shield

  3. Start Thunderbird, navigate to the Certificate manager and remove the Avast certificates

  4. Close Thunderbird and ensure it is fully shut down (no Thunderbird entries in Task Manager)

  5. Start Thunderbird, navigate to the Certificate manager and install the Avast certificates

  6. Close Thunderbird and ensure it is fully shut down (no Thunderbird entries in Task Manager)

  7. Enable Avast Mail Shield

  8. Start Thunderbird and retest

7

Also having problems sorting out Avast Free AV Mailshield and Thunderbird (both most recent versions). My first problem is FINDING the certificate to export. The blurb relates to an older version of Avast with Components listed - where do i find this certificate in the most recent version?