Avast Permium mail scanner causing Thunderbird to fail

Avast Free Antivirus / Premium Security
1

Thunderbird has not worked properly since December. I’ve tried multiple re-installs, config file changes, registry cleanups etc. I was about to change mail client when it occurred to me that Avast scans my mails. I stopped the mail client and Thunderbird worked fine. I then restarted the client but stopped outbound scans and it still works perfectly. So there is something in the outbound mail scanner that causes problems.

The errors are the usual “Server doesn’t support STARTTLS” and so on, even though all the accounts were configured correctly.

I’m on version 20.10.2442 build 20.10.5824.624 of Avast. On the latest Thunderbird client 78.6, on win 10 64 bit which is all up to date.

There are no errors reported in any of the Thunderbird logs.

2

It started failing after a while again even with outbound scanner turned off, so I’ve turned off the mail scanner completely and now all works fine. No problems at all since then. When I turn on the mail scanner it all stops working again. So at the moment I have no anti-virus on my emails.

3
So at the moment I have no anti-virus on my emails.
Most likely you have, unless you use a private mail server

All mail providers have spam/malware scanner on there servers scanning in/outgoing mails

4

Ah yes, thank you for reminding me. Stupid not to think of that ;D