Does Thunderbird give you the option to save the password when it asks for it? There is a hidden setting that controls this, but not sure that's the problem you have…

1. Go to Settings > General.
2. Click Config Editor at the bottom.
3. Type signon.rememberSignons into the search box.
4. The value of the settings shown there should be true (default). If something has caused any of the settings to be changed to false, a 'Reset' button with a counter-clockwise arrow will be available to the right of the 'Edit' button for the setting. Click that button to reset the setting to the default true value.

The Config Editor is documented here: https://support.mozilla.org/kb/config-editor

I have this problem too. The program remembers passwords when running. Every time I restart Thunderbird, I have to enter the passwords again. I also need to re-enter the password to post. I always check the box to Remember the passwords.

signon.rememberSignons is set to true. It has been set to true since I installed this version.

When I look at the saved logins, nothing is stored.

What the heck is going on?

I recently updated to the latest version because the old version I was running was tiny on my new 4K monitor. The old version held the passwords for years with no problems.

Don't ask me why, but his problem can apparently be fixed, at least in some cases, by deleting a pkcs11.txt file in the profile folder to make Thunderbird create it again.

The following article explains what's a profile and how to locate your profile folder: https://support.mozilla.org/kb/profiles-where-thunderbird-stores-user-data

1. Open the profile folder in the file manager
2. Quit Thunderbird
3. Delete pkcs11.txt
4. Launch Thunderbird

Let us know whether that worked in your case.

The only pkcs11.txt files I can find in the entire users directory are in Firefox directories. Nothing related to Thunderbird.

I followed the instructions in the link provided and didn't find anything there.

I checked another computer which has an older version of Thunderbird that works fine. I can't find that file for Thunderbird there either. Firefox has it on that computer too.

Do you see a prefs.js file and Mail and ImapMail folders there? Wondering whether you're looking in the right location…

The directory I'm taken to when I click on Open Folder in Application Basics has that directory and prefs.js in it. No pkcs11.txt file.

I also searched all profiles and the only pkcs11 files are in the Firefox directories.

On a wild hare I tried creating the pkcs11.txt file. It's 0 bytes. Closed Thunderbird, re-opened, had to enter the passwords again. Thought it had failed, but had to reboot the computer and after reboot it remembered the passwords! The file is still 0 bytes, but for some reason it now remembers. Why?

That's strange.

Interesting… I was going to ask whether you had Read & Write permissions to the profile folder, in case that could explain Thunderbird not being able to create the file there, but you must have if you could create the file manually yourself… Weird. But good to know. Thanks for the feedback.

I had checked write permission. I've run into that before with other programs.

I have another program that always throws an error when updating to a new version because there is a file the OS made read only, the installer can't delete it, and the OS won't let me change it, even as Administrator. So far it hasn't caused any problems, I just tell the installer to ignore and it continues to install without any problems.