I am not sure if this matters, but I just found another prefs.js file:

C:\Users\Mark\AppData\Roaming\Thunderbird\Profiles\yo9wz5hb.default 11.6 KB

C:\Program Files (x86)\Mozilla Thunderbird\defaults\pref 245 bytes

Hmm. The update I posted is no longer here.

I found some additional prefs.js files:

C:\Users\Mark\AppData\Roaming\Thunderbird\Profiles\yo9wz5hb.default 11.6 KB

C:\Program Files (x86)\Mozilla Thunderbird\defaults\pref 245 bytes

C:\Users\Mark\Documents\Thunderbird\yo9wz5hb.default 7.09 KB

• This is a copy of the Thunderbird folder that I made when this problem started (January ‎30, ‎2020)

re: 800MB Mail folder

This means you must have some emails in a pop account or Local Folders mail account.

re: Prefs file of 11.6 KB or 7.09KB in old folder location. This is too small, I would expect something closer to 70 KB.

Do you have another prefs.js listed below such as prefs-1.js ?

If no, then this means Thunderbird has no knowledge about the mail accounts and so cannot connect up to the pop mail account which still lurks in the : C:\Users\Mark\AppData\Roaming\Thunderbird\Profiles\yo9wz5hb.default\'Mail' folder

You should see the old pop mail account name folder and 'Local Folders' mail account.

I notice you say in previous comment: BTW: Last night I re-entered my account information in Thunderbird. I was hoping it would allow me to access my email, but it did not.

If you deleted it then recreate it. If it is still there please do the following:

Right click on the new pop mail account name in Folder Pane and select 'Settings' Select 'Server settings' Bottom of right pane look for 'Local directory' Make the window wider so you can see all the text for the Local directory. This is currently pointing to the new pop mail account which might have an additional number at the end eg: C:\Users\Mark\AppData\Roaming\Thunderbird\Profiles\yo9wz5hb.default\Mail\pop mail account name-1

click on 'Browse' button It will open on the current location for new pop mail account. Locate the original pop mail account name that is in the 'Mail' folder and select the original pop mail account name folder. click on 'Select folder' The new pop mail account will now point to the original pop mail account.

click on OK

Please report back on results.

It is though Thunderbird, which I have been using for a long time, were newly installed for first time. I need the Local folders messages.

With FF many times I have done profiles, profiles folders, and profiles.ini files manipulations. Always perfect. With Waterfox yesterday I did profiles, profiles folders, and profiles.ini files manipulations. Perfect.

With TB I did identical profiles-related manipulations; several times because results always are as though newly installed for first time. I need the Local folders messages.

The TB profiles folder contains subfolders and contains tons of files. TB is configured to point to it; profiles.ini specifies it. I assume that prefs- 1.js and prefs-2.js relate to the two email accounts. Despite sizes 20k and 24k of these prefs files, they contain nothing visible. There is no subfolder named Mail, probably because the accounts are not POP.

I need the Local folders messages. I would dig them out if I knew how to recognize them and how to handle them.

y112

re : I assume that prefs- 1.js and prefs-2.js relate to the two email accounts.

No

• 'prefs.js' is the file that contains all the preference settings.
• prefs- 1.js and prefs-2.js are old unused 'prefs' files which for some reason could not be used and so the old one was given a number and a new 'prefs.js' file was created.

re :There is no subfolder named 'Mail',

The 'profile name' folder will contain a folder called 'Mail' and it will contain all pop mail accounts , smart mailboxes (created when you use 'Unified' view) and 'Local Folders' mail account.

About nonexistent (yes) Mail subfolder : Today, in the always empty TB, I configured one of the two IMAP email accounts. Only thereafter did TB add a bare bones Local folders structure. Within the new profile folder now there is a subfolder ImapMail , plus a subfolder Mail (both nonexistent in original profile folder). I viewed file names inside Local Folders subfolder, and recognized files of same names that are in original profile base (yes) folder. I viewed file names a few layers deep inside ImapMail subfolder, and recognized that they have same kind of long numerical names as the four thousand such files in the original profile base (yes) folder.

So, it is reasonalbe to think that the original profile folder took a hit, such that contents of a previously existing Mail subfolder, and message files of a previously existing ImapMail subfolder, became contents of the original profile base folder. Probable consequence of one or more of many recent crashes of TB program.

I will continue trying to recover the original local messages.

I keep having the same problem. It seem that the Thunderbird application was automatically updated to the 68 version, cannot find any old profile anywhere in the way shown above. Have a got a new computer 64 bit, windows 10. My connections are there but no messages are shown in the original webmail either so have lost all the old incoming and sent messages befoere 12.4. Why did all this happen just yesterday if the update was done on the 12th? Cannot find the messages anywhere. Please help in a simpler way. Tried to restore the computer to an older date but no help.

Ulmus

Please start your own question so the original person who posted the question is not getting a load of emails from you or me that may not be the same problem.