How to Export Thunderbird Settings
The first part of exporting your Thunderbird settings is to know where these settings are kept. Every program on your computer will most likely have a folder in which your profile - where your settings are for that program - reside. For Thunderbird, this folder is usually located within the C drive of your computer, where the actual folder depends on which operating system you are using. For this article, we'll look at the popular Windows systems of XP, Vista, and the new Windows 7.
Windows Vista/7 users can find their Thunderbird settings here -
If you do not see the AppData folder, it may be hidden as it relates to a system folder. By default, all Windows system folders are hidden for the protection of the system and the user. To get this folder to appear, just go to the Folder Options, then select the View tab. Scroll until you find the option to 'show all hidden files, folders, and drives' and select it. Then hit 'apply' and then 'ok'. The AppData folder will now appear. If the old computer will be used by someone else, make sure to go back and select the default again.
Windows 2000/XP users can find their settings here -
C:\Documents and Settings\[User Name]\Application Data\Thunderbird\Profiles
As with Vista and 7, if you find that this folder is hidden, you can unhide it with the same technique described above.
Select the profiles folder and then right click on it. Choose the option to copy it. You can also do this through the folder's 'Edit' menu or through the keyboard short cut of CTRL + C. All three of these will copy the folder and it's contents. You will then need to paste this into the area or folder that you are using to back up your computer.
When you have finished with backing up the old computer, begin to transfer your files on to the new one. If you have not gone ahead and installed Thunderbird on the new computer, do so now. When the program has been installed, elect not to open it. Instead, go and locate the file paths form above. From your backup files, copy and paste the profiles folder into the new Thunderbird folder on the new computer.
Say 'ok' if asked if you want to overwrite or replace the current folder.
Remember that you will need to do this every time that you plan to either replace or reformat your computer, as the profile is updated every time that you use it.