Mozilla documents Thunderbird backup as a copy of the profile folder. Close Thunderbird first and copy the folder to another location or use the export tool. Mozilla states that a profile stored apart from the application is not a backup. Mail server data, a cloud stored profile and a profile on another computer do not count either. Mozilla does not mention the Local Folders name.
You want a backup of your Thunderbird Local Folders. Mozilla gives one answer for all Thunderbird data. Mail, passwords and settings live in a single profile folder.
Facts follow the Mozilla Support article on Thunderbird profiles. It does not describe Local Folders or name the files that contain mail.
Where does Thunderbird Store Your Data?
Thunderbird stores messages, passwords, preferences and changes in one profile folder. Thunderbird stores that folder apart from the application.
How to Open the Profile Folder?
- Open the ≡ menu, select Help and then Troubleshooting Information.
- Find Profile Folder under Application Basics. It is also labeled Profile Directory.
- Select the button in that row. Its label is Open Folder, Show in Finder or Open Directory.
When Thunderbird does not open, go to the folder by hand.
- Windows. %APPDATA%\Thunderbird\Profiles\ with hidden AppData files shown if needed.
- macOS. Library, then Thunderbird, then Profiles. Press the Option key in the Go menu of Finder to show Library.
- Linux. The .thunderbird folder in your home directory with hidden files shown.
Mozilla says that release and ESR profile folder names end in default-release. Mozilla describes a plain default folder as an empty placeholder.
How to Backup the Profile?
- Close Thunderbird.
- Copy the profile folder to another location.
Mozilla names the export tool in Thunderbird as the other option. Copy the profile again at regular intervals because Mozilla recommends frequent backups.
What does Mozilla Not Count as a Backup?
- Mail server data.
- Your local profile in its normal location.
- Profiles stored on another computer.
- Profiles stored in cloud storage.
Mozilla states that cloud synced profiles work in many cases. It does not treat them as backups.
How to Restore a Backup?
Close Thunderbird first. Replacing a profile folder needs an exact name match, including the random eight character string. Otherwise create a new profile and copy the contents of the backup into it.
Mozilla warns against opening one profile from several Thunderbird instances, computers, file shares or cloud sync at the same time. It states that this risks corruption and permanent data loss.
What does Mozilla Not Say?
- Anything about Local Folders by that name.
- Names of the files that contain mail.
- Steps for the export tool.
Related reading: how to migrate Thunderbird mail to a new computer and how to reindex Thunderbird folders.
Frequently Asked Questions
How do I Backup Thunderbird Local Folders?
Close Thunderbird and copy the profile folder to another location. Mozilla also names the export tool as an option.
Where is the Thunderbird Profile Folder?
Open Help and Troubleshooting Information. Select the button next to Profile Folder under Application Basics.
Is a Cloud Synced Profile a Backup?
No. Mozilla states that a profile in cloud storage is not a backup.
Can I Backup While Thunderbird is Open?
No. Mozilla states that you must close Thunderbird before copying or restoring the profile.
Does Mozilla Mention Local Folders?
No. Mozilla describes the profile folder and does not use that name.
Key Takeaways
- All Thunderbird data lives in one profile folder.
- Close Thunderbird before you copy or restore the profile.
- Mail server data and cloud synced profiles are not backups.
- Restore needs an exact folder name match or a new profile with copied contents.
- Mozilla does not mention Local Folders by name.
Sources and References
Facts follow Mozilla Support.
- Thunderbird profiles and where Thunderbird stores user data (Mozilla Support) support.mozilla.org