How to recover deleted Thunderbird messages

In this article, we will describe all the existing methods of message recovery for the popular free email client Mozilla Thunderbird in details. Starting from undelete from the Recycle Bin and ending with data recovery from the hard drive. All methods described in this article are applicable for recovering messages stored on a local PC HDD. So, for all POP accounts, as well as for those IMAP accounts for which the option "Keep messages in all folders for this account on this computer" is enabled (enabled by default).


Where Thunderbird stores data (messages, contacts, passwords, settings, etc.)

Thunderbird stores all the data in the so-called Profiles. When you first start the program a default profile is being created. You can also create additional profiles. Profiles are stored in a folder C:\Users\UserName\AppData\Roaming\ Thunderbird\Profiles The folder containing the default profile files has a name like xrmwa7b9.default, where xrmwa7b9 is a random sequence of characters.

If you are using the portable version of Thunderbird, then your profile will be located in the folder X:\PathToThunderbirdPortable\Data\profile where X:\PathToThunderbirdPortable is the path to the folder where you installed Thunderbird Portable.

Note: The profile folder has a Hidden attribute, so you must enable the display of hidden folders and files in the Windows Explorer settings.

Tip: To back up your Thunderbird data, close the program and copy the profile folder to a safe place. For example, to an external hard drive.

In what format does Thunderbird store data

A user profile in Thunderbird contains a set of files and folders. Here is a description of some of the files:

  • abook.mab, history.mab - Thunderbird address book files
  • logins.json - encrypted password file
  • cert8.db or cert9.db - file of saved security certificates
  • key3.db or key4.db - file of encryption keys
  • panacea.dat - mail folder cache
  • prefs.js - main Mozilla Thunderbird configuration file
  • user.js - additional configuration file

Messages are stored in the Mail and ImapMail folders. The Mail folder contains messages from POP accounts, RSS feeds, Local Folders and Smart Folders. The IMAPMail folder contains messages from IMAP accounts. The data for each account in the Mail or ImapMail folder is stored in a separate subfolder.

Mozilla Thunderbird can store messages in two different formats - MBOX and MAILDIR. In MBOX format, all messages in a folder are stored in one file. The name of the mbox file matches the name of the folder. The file of the same name with the extension .msf contains message indices to speed up the program. In the MAILDIR format, each message is stored in a separate file (EML format).

Thunderbird uses the MBOX format by default. The MAILDIR format is considered experimental and is recommended only for experienced users. That is, if you did not specifically instruct Thunderbird to use the MAILDIR format, then your messages will be stored in MBOX format files.

Recovering messages from Recycle Bin (Trash folder) Thunderbird

This method seems obvious and requires no attention, but some people simply forget about it.

To recover deleted Thunderbird messages from the trash, follow these steps:

  1. Select your Thunderbird account
  2. Open the Trash folder and find or select the message you want to recover
  3. Right-click on the message and select Move To. Select the Thunderbird folder in which you want to place the recovered message.
Recover Thunderbird messages from the Trash folder

Tip: You can simply drag a message from the Trash folder to another folder using Drag & Drop. If while holding down the Ctrl button, a copy of the message will remain in the trash. You can also select several messages in the basket. To do this, when you click on a message, hold down the Ctrl or Shift button.


  • the easiest way to recover a deleted message
  • does not require additional software


  • this method does not work if you empty the trash

Manual recovery of permanently deleted messages from an MBOX file

Even if you empty the bin, you can still recover your messages. The fact is that when you delete a message, it is not actually deleted, but only marked as deleted. The actual deletion of a message from the mbox file occurs when you compress the folder. Actually, that is why they compress folders.

You will need a text editor capable of opening very large files. For example, free Notepad++ .

Follow these steps:

  1. From the Mozilla Thunderbird menu, select Help -> Troubleshooting Information. Open Troubleshooting Information tab
  2. In the Troubleshooting Information tab that opens, click the Open Folder button. A folder with your profile will open. Open Thunderbird profile folder
  3. In the Windows Explorer window, go to the Mail or ImapMail folder and then go to the folder of the account you need.
  4. Locate the MBOX file of the message folder in which you want to restore. Right-click on the file and select Edit with Notepad++. Open MBOX file in Notepad++
  5. Find the deleted message. In the line 'X-Mozilla-Status: 0009' (instead of 0009 there may be 0008, 0018, 0019 or rarely another value) replace 0009 with 0000. Press Ctrl + S to save the changes and close Notepad++. Edit X-Mozilla-Status in Notepad++
  6. In Mozilla Thunderbird, right-click on the folder and select Properties. In the Folder Properties window, click the Repair Folder button to create a new folder index. Repair Thunderbird folder


  • allows you to recover messages even if you empty the trash


  • there is a risk of damaging the mbox file
  • it takes a lot of time if you need to recover a lot of messages
  • additional software required

Recovery of permanently deleted messages using the RecoverDeletedMessages extension

If you are using Mozilla Thunderbird version 52 or earlier, then you can use the add-on RecoverDeletedMessages. Unfortunately, at the time of writing, the extension is not compatible with newer versions of Thunderbird.

Follow these steps:

  1. Download  the extension file
  2. From the Mozilla Thunderbird menu, select Tools -> Add-ons Open Add-ons Manager
  3. On the Add-ons Manager page that opens, click on the Tools for all add-ons button and select Install Add-on From File. Select the extension file and click Open. In the Software Information window, click Install Now. Restart Mozilla Thunderbird Install add-on from file
  4. From the Thunderbird menu, select File -> Offline -> Work Offline Work Offline
  5. Right-click on the message folder in which you want to recover and select Recover deleted messages. Recovered messages will be placed in the Deleted_emails_0 subfolder of the selected folder


  • allows you to recover messages even if you empty the trash
  • a much simpler method than the previous
  • there is no risk of damaging the MBOX file


  • additional software required
  • extension is not compatible with Mozilla Thunderbird versions 60 and higher

Rebuilding the Global Database

The Global Database allows Thunderbird to perform a quick message search. The corruption of the global-messages-db.sqlite file may result in some or all of the emails disappearing from Mozilla Thunderbird folders. In that case, you can create a new global-messages-db.sqlite file.

To do so, follow these steps:

  1. In Mozilla Thunderbird menu select Help -> Troubleshooting Information.
  2. In the Troubleshooting Information tab click the Open Folder button. This action will open a folder with your profile.
  3. Quit Mozilla Thunderbird.
  4. Find the global-messages-db.sqlite file in your Thunderbird profile folder and move it to a different folder on a hard drive.
  5. Start Thunderbird. The process of indexing emails and creating the new global-messages-db.sqlite file will start automatically and may take some time. You can monitor the indexing process using the Activity Manager tool (select Tools -> Activity Manager in the Thunderbird’s menu).

As a bonus benefit, you may notice the increase in Thunderbird’s productivity, since the global database would be defragmented.

Thunderbird folder repair and index file recovery

Sometimes you may encounter a problem when some messages simply disappear from the folder but you know for sure that you did not delete them. The problem can be caused by damage to the folder index file (.msf file). To create a new MSF file, right-click on the folder and select Properties. In the Folder Properties window, click the Repair Folder button.

Repair Thunderbird folder

Recovering messages from a local hard drive using Recovery Tool for Mozilla Thunderbird

The methods described above will be ineffective if the folder has been compressed (Thunderbird periodically compresses the folders to save disk space) or if you use the MAILDIR format. Violation of the logical structure of the hard disk, formatting the disk, deleting the partition makes it impossible to use the methods described above. In these cases, messages can be restored with Recovery Tool for Mozilla Thunderbird.

Follow these steps:

  1. Download, install and run Recovery Tool for Mozilla Thunderbird
  2. Click on the HDD tab, select drive C: and click on the Find and recover lost emails button; wait until the disk scan Find and recover lost emails
  3. Select the messages you want to recover or press Ctrl + A to select allSelect all items
  4. Click the Save recovered emails button, select the folder in which you want to save messages and click Save; do not save messages on the disk from which you recover messages ; otherwise, not all messages can be restoredSave recovered emails
  5. Using Drag & Drop, drag and drop messages from the Windows Explorer folder to the Mozilla Thunderbird folder Import of eml files using drag & drop

Try to restore emails by the video given below:

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