Thunderbird 78 FAQ (Mozilla Thunderbird email client version 78 issues and resolution)

Mozilla Foundation ^ | July 2020 | Mozilla Support

[dayglored]

Dayglored Note: Many Thunderbird users are finding operational issues after updating to Version 78 (including me). This FAQ addresses some of them, in particular the deprecation of TLSv1.1 and earlier, which will cause Thunderbird to be unable to send/receive email from some mail servers.

I have copied the FAQ content regarding that particular issue below. The whole page is useful, and is found here: https://support.mozilla.org/en-US/kb/thunderbird-78-faq

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After upgrading to Thunderbird 78, I cannot get or send email messages.

One reason why this might happen is when your email provider is using outdated security protocols. Thunderbird takes protecting the privacy and security of your communication serious. That is why, by default, Thunderbird 78 will not connect to servers that do not support the modern TLS 1.2 connection security protocol. So if your email provider only supports the outdated security protocols TLS 1.0 or TLS 1.1, downloading (receiving) and sending emails will not work by default. If you really need to connect to such mail servers with outdated security, or if you want to check if this is the cause of your problem, you can temporarily re-enable the older security protocols in Thunderbird settings.

How to enable outdated security protocols TLS 1.0 and 1.1

1. Open Config Editor (about:config)
   • ≡ > OptionsPreferences > Find in OptionsPreferences
   • In the searchbox, type: about:config, then press Enter.
   • Click on the button Config Editor… in the search result.
2. In the about:config dialog, search for: security.tls.version.min
3. Double-click on the found preference security.tls.version.min and change its value to 1, then press Enter.
4. Restart Thunderbird and try to download your messages.

If you can download your messages after changing this preference:

• Please inform your email provider to upgrade the security protocols on the server to support TLS 1.2.
• Revert the preference security.tls.version.min to its original value as soon as possible by repeating the above procedure, then right-click on the preference and choose Reset from the context menu.

[dayglored]

> They should at least have an option to revert back to the old version if someone is having serious problems.

I agree, there should be an easy way to roll back. Failing that, regular backups help -- Apple's TimeMachine is ideal for rollback.

But if you don't have a recent backup, Mozilla has all the old versions available for download and install:

https://ftp.mozilla.org/pub/thunderbird/releases/

[daniel1212]

In contrast to much of today. My first car was a 63 T-bird. But thank God for what we have, and engines that last far longer.

[daniel1212]

I used T-bird 78.4, with no extensions (yet) and I surmise an extension is the problem in your case. Mine (with personal content redacted) looks like

[dayglored]

BTW, if you want to get a more recent version than the one Ubuntu is posting, go here: https://ftp.mozilla.org/pub/thunderbird/releases

For example, for Ubuntu 64-bit: https://ftp.mozilla.org/pub/thunderbird/releases/78.4.0/linux-x86_64/en-US/

Of course, it's just the application as a compressed tarball. The extra stuff to hook it into the OS and your favorite desktop environment is manual since that's individualized.

[minnesota_bound]

For future updates or reinstall, copy your email off to a safe location.
Unfortunately Thunderbird does not make it easy such as Backup> Account but has you do searches on the internet on how to backup and import the email.

You gotta be a geek to do it !

Profiles - Where Thunderbird stores your messages and other user data
https://support.mozilla.org/en-US/kb/profiles-where-thunderbird-stores-user-data

Moving Thunderbird Data to a New Computer
https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer

The random yccklof6.default name is different for your install.

Open Thunderbird> Tools> Account Settings> Local Folders>
Local directory>
C:\Users\ Your name \AppData\Roaming\Thunderbird\Profiles\yccklof6.default\Mail

Your old email is there. You can copy and paste the folders into your new folder from the new install.

Inbox.sbd
Sent.sbd
Drafts.sbd
Templates.sbd

[upchuck]

Been running Tbird for years without any problems.

Currently running 60.2.1 on Windows 7. Flawlessly.

Charlie Brown

PS: My philosophy regarding updates: why fix something if it ain’t broke? Which is why I’m running Win 7 instead of Win 10.

[Mr. Blond]

You can pry Eudora 7 from my cold, dead hands.

[ImJustAnotherOkie]

Ahhh..Windows7.

[dayglored]

> You can pry Eudora 7 from my cold, dead hands.

I used Eudora (6 as I recall) for years, long ago. Nice client.