Avast may block Thunderbird updates

Avast and AVG antivirus products may block updates in Thunderbird. Avast is testing a beta version of its applications that attempts to resolve the issue.

Users of Avast and AVG antivirus solutions that use the open source email client Thunderbird may face another problem. Earlier versions of Avast and AVG products on Windows caused severe crashes of the Firefox web browser earlier this month. Mozilla had to rush a release, blocking older drivers of the antivirus solutions to prevent crashes in the Firefox web browser.

Now it is Thunderbird. This time, it is not crashes that Avast and AVG software is causing, but issues with the email client's updating system.

The Mail Shield component of Avast and AVG products, designed to block malicious emails from reaching a user's inbox, appears to be the culprit. The Thunderbird team confirmed the issue on its Twitter account, stating that the issue is caused by connection issues of Avast's and AVG's Mail Shield component.

Sören Hentzschel discovered that the issue dates back to at least July 2022. A user published a bug report on the Avast Forum, stating that Avast blocked automatic updates in Thunderbird.

Avast is testing a Beta version at the time, but has not published a stable new update that addresses the issue.

Thunderbird users may want to check the installed version of the email client to find out if they are affected. The latest version, at the time of writing, is Thunderbird 102.3.3.

Thunderbird users who are affected by the issue may disable the Shields component of the Avast or AVG software temporarily to update Thunderbird. Selecting Menu > Help > About Thunderbird should download and install the latest version once Shields are down.

Another option that users have is to uninstall Avast or AVG software on their device. On Windows, fallback is provided by Microsoft Defender.

Avast has not revealed a release date for the fixed version. The beta version was released on September 22.

Now You: which security solution do you use on your machines?

Avast may block Thunderbird updates