Corbett

Thunderbird Backup Tool

Corbett Thunderbird Backup Tool opens the Mozilla Thunderbird profile already on a Windows PC and saves every account, Local Folders included, as PST, MBOX, EML, MSG, PDF, HTML, CSV or TXT. No passwords are asked for, because the mail is copied from the profile on disk.

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4.9 out of 5 from 698 reviews

Mail comes straight from the Thunderbird profile on this PC. Nothing is uploaded to Corbett.

Free demo, scanned clean on VirusTotal and a 30-day money-back window.

Lifetime licence from $99 Free trial saves 10 emails per folder

Profile facts

Thunderbird Backup Tool for Every Local Profile

Thunderbird keeps all mail inside one profile folder under AppData. A failed update, a dying disk or a corrupt .msf index can hide years of folders overnight. Thunderbird Backup Tool copies that profile into files that open without Thunderbird, so the mail survives whatever happens to the program.

Comes across

Folder tree
Attachments
Inline images
Signatures
Message dates
Read/unread status
Full headers

Folders backed up

Inbox
Sent
Drafts
Archives
Junk
Trash
Local Folders

Saves as

PST
MBOX
EML
MSG
PDF
HTML
CSV
TXT

Not included

Add-ons and themes
Message filters
Saved passwords
Calendar events

Where Thunderbird keeps the profile

In Thunderbird, open Help, then Troubleshooting Information, then Profile Folder. Another route is typing %APPDATA%\Thunderbird\Profiles in the Windows Run box. IMAP accounts sit under ImapMail and POP or local mail under Mail. The tool finds this path on its own.

Export Thunderbird archive folder

Core features

Thunderbird Backup Tool Across Five Screens

From profile detection to a finished file, the run as it appears in the wizard.

Detect

Load the Thunderbird Profile

Go to Open, Desktop Email Clients, Thunderbird Accounts and the configured profile appears with every account inside it. Nothing has to be typed, because the mail is taken from disk rather than from a server. Several profiles on one PC show up as separate entries.

Default and custom profile paths found
IMAP, POP and Local Folders handled alike
Several Thunderbird profiles in one session
Works even if Thunderbird is closed

Thunderbird folder tree with selection checkboxes

Folder selection

Choose the Thunderbird Folders to Save

Every account and its folders appear in a tree with message counts, including Archives organised by year. Greyed out folders can be skipped and empty ones hidden before the run.

Accounts, folders and subfolders all selectable
Counts shown beside folder names
Option to skip greyed out folders
Leave Junk and Trash in Thunderbird

Message preview

Preview Thunderbird Mail Before Export

Check any message from the profile before it is saved. Next to the standard view sit four analysis tabs, useful when Thunderbird mail has to serve as evidence or an audit record.

Content keeps the body, sender, recipients and subject together
Message header follows Received lines down to the sending server
Properties shows size, priority and every enclosure
Hex and raw message bring back the original message source

Selective backup

Filter Thunderbird Mail Before Export

Search panes for folders and for messages work independently. Export one client's thread, one financial year or one mailing list from a cluttered Thunderbird profile without touching the rest.

From and To dates on the export
Sender, subject or words inside the body
Messages carrying attachments only
Size cap for oversized mail
Repeat copies skipped
Files kept, message text dropped

Output options

Save Thunderbird Mail as Files or Upload It

Once the preview looks right, choose a folder, an external drive or a NAS share. Thunderbird mail can also be pushed to a live account, the common choice when a user moves to Outlook or Microsoft 365.

PST for Outlook, plus MBOX, EML and MSG copies
PDF, HTML, CSV or TXT for printing, records and search
Upload Thunderbird folders to Gmail, Microsoft 365 or another IMAP host through the Thunderbird Migrator
Save attachments, addresses or phone numbers alone, see Download attachments from Thunderbird for the manual way

Before starting

Thunderbird Profile Checks Before Backup

Thunderbird Backup Tool works on files on disk, so a few profile checks on the PC matter more than any password.

Check first

Compact folders before the run

Use File, then Compact Folders in Thunderbird. Deleted mail that still sits inside the MBOX files is cleared out, so the backup is smaller and holds only real messages.

IMAP accounts

Download messages for offline use

With IMAP, Thunderbird may keep only headers locally. Turn on offline sync under Account Settings, Synchronization and Storage, so full messages are in the profile before the backup.

Moved profile

Profiles on other drives

A profile copied to a second disk or a USB stick can still be backed up. Point the tool to the folder holding prefs.js and the account list loads from there.

Folder or speed problems inside Thunderbird are covered in Thunderbird not showing folders and Thunderbird running slow.

Free demo

Test Thunderbird Backup Tool With Real Mail

Install the demo, let it find the Thunderbird profile and export one folder. Open the output before paying anything.

Download free demo

Before purchase

Free Export Add-on vs Thunderbird Backup Tool

The free ImportExportTools NG add-on exports single Thunderbird folders to EML, MBOX, HTML or PDF from inside the program. For one quick export that is plenty. Here is where a dedicated backup tool goes further.

Task	ImportExportTools NG	Thunderbird Backup Tool
Cost	Free	$99 one time
Export one folder to EML or MBOX	Handles it well	Does it too, the price covers the rest
Outlook PST output	Not available	PST plus seven other formats
Filter by date, sender or size	Folder level only	Fine-grained filters before export
Header, hex and raw views	Thunderbird's own source view	Four analysis tabs in the preview
Thunderbird must be running	Yes, the add-on works inside it	No, the profile is opened directly
Several profiles or accounts	One folder or account at a time	All accounts in one run
Upload to Gmail or Microsoft 365	Not supported	Direct IMAP upload built in

Green rows mark where the free add-on holds its own.

For a quick single-folder export, ImportExportTools NG is free and works well. The steps to Export MBOX from Thunderbird are covered in that guide.

Specifications

Thunderbird Backup Tool Hardware Needs

Download details

Released: Dec 2020
Download size: 87.4 MB
Trial limit: 10 emails per folder
Delivery: Download link and key by email
Licence: Lifetime, up to 5 machines

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System

Hard disk: 150 MB to install, plus room for output
RAM: 4 GB minimum
Processor: 1 GHz, 2.4 GHz advised
Rights: Run as Administrator
Thunderbird: Profile on the same PC

Supported editions

Windows 7, 8, 10 and 11, 32-bit or 64-bit, with Windows Server 2008 to 2025 supported as well.

No macOS or Linux build.

Corbett has built Windows email utilities since 2020. Thunderbird Backup Tool questions are answered by its own engineers.

Working process

See Thunderbird Backup Tool Export a Profile

Prefer step-by-step pictures? The Thunderbird backup guide walks through a profile export.

Common questions

Thunderbird Backup Tool FAQs

Profiles, offline mail, formats and the limits of a disk-based backup.

How do I back up Thunderbird emails with this tool?

Install the tool, open Desktop Email Clients and choose Thunderbird Accounts. Your profile loads automatically. Preview the folders, select a format and start the export.

Do I need my Thunderbird or email password?

No. The tool takes mail from the profile on your disk, not from the mail server, so no account password is involved.

Where is my Thunderbird profile on Windows?

Usually under %APPDATA%\Thunderbird\Profiles in a folder ending in .default-release. In Thunderbird, Help, Troubleshooting Information, Profile Folder opens it directly.

Some IMAP folders come out empty. Why?

Thunderbird only had headers for them. Turn on Keep messages for this account on this computer under Synchronization and Storage, let Thunderbird download, then run the backup again.

What if the profile sits on an old PC?

Yes. Copy the profile folder from the old computer, then point the tool at it. Every account inside loads as if Thunderbird were still installed there.

Will my Thunderbird folders keep their order?

Yes. Accounts, Local Folders, Archives by year and every subfolder come out in their original order. A flat single folder is optional.

Does it handle several Thunderbird profiles?

Yes. Every profile found on the PC is listed and they can run together, handy on a shared family computer.

Are attachments and contacts kept?

Attachments stay with every message. Extract can also pull attachments, email addresses and phone numbers into separate files, which covers most contact lists.

Is Thunderbird required to be installed?

The tool needs the Thunderbird profile, not the running program. With Thunderbird installed it is found automatically; a copied profile folder can be loaded by hand.

Can a repeat backup add just recent Thunderbird mail?

There is no incremental mode. Set a start date matching the last backup and turn on duplicate skipping, so a repeat run stays quick.

How large a Thunderbird profile can it export?

No. Profiles of 30 GB and more export in the full version. Because mail comes from disk, speed depends on the drive, not on a mail server.

Can I move Thunderbird mail to Outlook or Gmail?

Yes. Save to PST and open it in Outlook, or upload folders straight to Gmail, Microsoft 365 or any IMAP account from the same screen.

Does my Thunderbird mail leave my PC?

Only if you choose an online destination. For file backups everything stays on your own drives and Corbett receives nothing.

Does it support macOS or Linux?

No. It is a Windows program. Mac or Linux Thunderbird profiles can be copied to a Windows PC and backed up there.

What does the Thunderbird demo allow?

It finds the profile, shows the full folder list and unlocks preview and filters. Output is capped at the first 10 emails of every folder, enough to judge the result.

Step by step

Thunderbird Help Guides and Tools

Guides for common jobs around a Thunderbird profile backup.

Exporting from Thunderbird

Moving Thunderbird

Fixing problems

Every supported mail source is listed on the email backup software page. To transfer a full Thunderbird profile to another mail service, use the Thunderbird Migrator. Loose MBOX files can become PST, PDF and more with the email converter tool. Putting saved Thunderbird mail into an online account again is handled by the email recovery software. To look inside an MBOX without exporting, use the free email viewer software. More Thunderbird reading: Export Thunderbird archive folder and Extract email addresses from Thunderbird. Related tools: AOL backup tool, Gmail backup tool, Outlook.com backup tool, Yahoo backup tool and Webmail backup tool.

User testimonials

Thunderbird Backup Tool Reviews

From 698 reviews of the Corbett backup wizard that opens Thunderbird profiles.

4.9 out of 5

Collected across 698 reviews from software portals and customer email. The quotes below are reproduced unchanged.

Recommended by a friend

It is an amazing software to download all Thunderbird emails to a number of applications. One of my friends recommended this tool to me for its efficient and fast backup process, and it worked well.

Lawrence Smith

Many formats, no downtime

I loved the Mozilla Thunderbird backup tool because it was able to backup my entire Thunderbird emails in numerous file formats. Also, it can save data files without any downtime.

Katherine William

Bought the licensed edition

The software's advanced functionality let me buy its licensed edition. It is such a fantastic toolkit that works with my expectations. Also, it allows you to store data on over 100 platforms.

Taniya Rao

Get started

Protect a Thunderbird Profile Today

Download the demo, let it find the Thunderbird profile and export a sample from every folder. The full version costs $99 once, and refunds are available for 30 days.

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87.4 MB · Windows 11 to 7 and Windows Server 2025 to 2008 · 30 day money back