Migrating messages and profile to a new PC or reinstalling TB
The steps in help document at https://support.mozilla.org/en-US/kb/moving-thunderbird-data-to-a-new-computer are no longer sufficient when migrating, now that TB creates a new profile ID a teach installation.
When TB is installed, it creates a new profile in %APPDATA%\roaming\Thunderbird\Profiles\. If you copy across the old profile, replacing the entire Thunderbird folder tree, TB will open OK at first, but if closed will not reopen (a blank frame opens with no content or menus, or a small window with an error message).
To resolve, close TB, navigate to the profile folder "%APPDATA%\roaming\Thunderbird\Profiles\[profileID].default\, and open the file prefs.js in a text editor. Then search for all references to a profile path like this, and update the profileID for any that are not the correct new ID. Save prefs.js and reopen TB, which should now behave correctly.
The reason for this issue is that, since TB version 68, every new install of TB now creates a new profileID. When you copy the old profile it will open OK, but on closing TB adds key entries that reference the old ID, not the new. This causes pref.js to fail to load next time and hangs the program. See https://support.mozilla.org/en-US/kb/dedicated-profile-thunderbird-installation for more info on profileIDs.
Wubrane rozwězanje
Some more detail for those not familiar with text searching in Notepad.
First, note the profile ID that is active in your new installation. It's the folder name in the profiles directory which ends with ".default". Copy/paste it somewhere convenient.
Then locate the prefs.js file in the \profiles\ directory, right-click, open with, choose your text editor, for example notepad.
In most text editors, Ctrl-F opens a search dialog. search for \\profiles\\, and for each instance, check that the profile ID is the one you saved earlier. If you've just migrated it won't be. If so, replace with the correct one. You may find several lines to change, such as:
user_pref("mail.root.none", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail"); user_pref("mail.root.pop3", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail"); user_pref("mail.server.server1.directory", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail\\pop.dial.pipex.com"); user_pref("mail.server.server2.directory", "C:\\Users\\[username\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail\\Local Folders");
If you've migrated to a new PC, or reinstalled Windows, your username may also have changed. So check that too. By default Windows uses five characters from your name, in my case "jstua".
Toś to wótegrono w konteksće cytaś 👍 0Wšykne wótegrona (2)
this might be useful if you documented the preferences you changed.
Wubrane rozwězanje
Some more detail for those not familiar with text searching in Notepad.
First, note the profile ID that is active in your new installation. It's the folder name in the profiles directory which ends with ".default". Copy/paste it somewhere convenient.
Then locate the prefs.js file in the \profiles\ directory, right-click, open with, choose your text editor, for example notepad.
In most text editors, Ctrl-F opens a search dialog. search for \\profiles\\, and for each instance, check that the profile ID is the one you saved earlier. If you've just migrated it won't be. If so, replace with the correct one. You may find several lines to change, such as:
user_pref("mail.root.none", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail"); user_pref("mail.root.pop3", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail"); user_pref("mail.server.server1.directory", "C:\\Users\\[username]\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail\\pop.dial.pipex.com"); user_pref("mail.server.server2.directory", "C:\\Users\\[username\\AppData\\Roaming\\Thunderbird\\Profiles\\[profileID].default\\Mail\\Local Folders");
If you've migrated to a new PC, or reinstalled Windows, your username may also have changed. So check that too. By default Windows uses five characters from your name, in my case "jstua".