Copying all your Thunderbird email data to a new PC

Copying all your Thunderbird email data

You can copy your data to a new computer (or other location) by copying your Profile Folder and then telling Thunderbird where to find your Profile Folder. 

1. Find the existing name and location of your Profile Folder by selecting "Help > Troubleshooting Information" in the Thunderbird menu. Then look for "Profile Folder" and click on the Show Folder button. This will display the path of names starting with parent folders and ending with the name of your Profile Folder.
2. Use the facilities of your operating system to highlight and then copy this profile folder, with its contents, to a new computer or other new location (with a new name, if you wish). Be sure you are not copying a profile folder while Thunderbird is running and using that folder. If you have a large amount of email data, the copying process may take a long time.
3. Tell Thunderbird where to find your Profile Folder, by using the Profile app. For example, in Windows 10, a) Close Thunderbird, b) Right-click the Start icon, c) Click Run, d) Enter this in the Open box (without the quote signs): "thunderbird.exe -p" ,
   e) Click OK
4. In the Profile app, create a new Thunderbird Profile for your new Profile Folder: a) Click the Create Profile button, b) Click Next, c) Enter a name for your new Thunderbird Profile (this does not need to be the same as the name of your Profile Folder), d) Click the Choose Folder button, e) Navigate to and select your new location's Profile Folder that was set up in Step 2, f) Click Select Folder, g) Click Finish 

You will now see a Profile app window that displays your new profile in the list of your profiles. (You'll probably have at least one other profile, even if it's just called "default".)
If each time you start Thunderbird you want to select from a choice of profiles, uncheck the "Use the selected profile without asking ..." box.
To automatically use a specific profile, select that profile and check the "Use the selected profile without asking ..." box. (You can always start the Profile app again, to change this setting.)

Close the Profile app by clicking the Exit button.