Old versions can be found here:

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

But all versions up to and including 53 have worked fine for me, on mulitple computers, both Windows and Linux.

Check your firewall and security software.

I have turned off both windows defender and Kaspersky, but still cannot open my mail.

52.1.1 is now available.

Turning off AV sometimes is not enough. A more thorough process is Start *Windows'* safe mode with networking enabled - win10 https://support.microsoft.com/en-us/help/12376/windows-10-start-your-pc-in-safe-mode - win8 https://support.microsoft.com/en-us/help/17076/windows-8-startup-settings-safe-mode - win7 https://support.microsoft.com/en-us/help/17419/windows-7-advanced-startup-options-safe-mode#start-computer-safe-mode=windows-7 - XP https://www.microsoft.com/resources/documentation/windows/xp/all/proddocs/en-us/boot_failsafe.mspx

Still In Windows safe mode, start thunderbird in safe mode - https://support.mozilla.org/kb/safe-mode-thunderbird

Does problem go away?

Sorry Wayne, did all that and still it will not open my mail. It downloads the headers but will not open the mail when I click on "download the rest of the message".

> not open the mail when I click on "download the rest of the message". This should be fixed in 52.1.1

Thanks Wayne!

When Thunderbird updated to 52.1.1 Thunderbird changed completely. Junk filtering is non-functional. My theme is gone. My backup program (Retrospect) began throwing up on Thunderbird files with odd "can't access" messages that I've never seen in the 17 years I've been using Thunderbird. What a mess. I want to go back to version 45.8.0.

I want to go back a version prior to 53. as it keeps resetting my language to French! When I go to https://ftp.mozilla.org/pub/thunderbird/releases/ what do I do next.

Similar problems. So exactly how do i roll back to earlier version?

curtwh said

Similar problems. So exactly how do i roll back to earlier version?

This has already been posted - Download a release at https://support.mozilla.org/en-US/questions/1160158#answer-968433

kormond said

I want to go back a version prior to 53. as it keeps resetting my language to French! When I go to https://ftp.mozilla.org/pub/thunderbird/releases/ what do I do next.

Please go to help, troubleshooting. What do you see at "User Agent"? Please go to help, about. What "update channel" is shown?

Zenos said

Old versions can be found here: https://ftp.mozilla.org/pub/thunderbird/releases/ But all versions up to and including 53 have worked fine for me, on mulitple computers, both Windows and Linux. Check your firewall and security software.

This link gives me a list of previous versions. Does NOT give instructions on how to install/rollback.