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How Do I Move Thunderbird to a New Computer?

Just say the secret word.

Thunderbird download page.
Thunderbird download page. (Screenshot:
Moving email from one machine to another is a snap when you're using Thunderbird as your email program. I'll show you how.
My laptop is having problems, and I want to copy off my email before it dies and move that to another machine. How do I do that? I use Thunderbird.

That’s a question I asked myself one day some time ago.

After returning from a road trip, my laptop started to act “funny”. I realize that’s not the best of descriptions, but it’s the most accurate I could come up with before further diagnosis.

It was running, and I wanted to start some potentially multi-hour diagnostics, so I needed to move my email to my desktop machine.

This is one of the reasons I love (and recommend) Thunderbird: this is really, really easy. Easier than most email programs I know.

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Moving Thunderbird

Thunderbird stores all your information in what it calls a “profile” — a folder that contains everything. All you need do to move your Thunderbird email is to locate the profile on the old machine and copy it in its entirety to the profile location on the new machine.

The secret word: profile

Thunderbird uses what it calls “profiles” to locate all of the information associated with your email. Your profile folder has everything: mail, mail folders, email accounts, contacts, installed extensions, and so on.

This makes copying your Thunderbird-based email from one machine to another a simple process.

  • Close Thunderbird on the source machine (the machine on which you currently have your email).
  • Install Thunderbird on the destination machine (the machine on which you want to have your email).
  • Run it once on the destination machine, configure nothing, and exit.
  • Locate the profile folder on the destination machine.
  • Erase the contents of the profile folder on the destination machine.
  • Locate the profile folder on the source machine.
  • Copy the contents of the entire profile folder and all subfolders from the source machine to the destination.
  • Run Thunderbird on the destination machine.

That’s all there is to it.

Get Thunderbird

I’m going to assume that you’re running the latest version of Thunderbird, as I was.

Download and install the latest version of Thunderbird on the machine to which you want to move your email.

Run Thunderbird, and it’ll prompt you to begin configuring your email. Cancel that. We do not want to configure anything. With that out of the way, close Thunderbird.

This step was necessary to cause Thunderbird to create the profile folder into which we’re about to copy our information.

While you’re at it, close Thunderbird on the source machine.

Finding profiles

There’s a support article on locating profiles that covers it for other operating systems, but in a nutshell, here’s what worked for me on Windows.

In the folder


(where “LeoN” is replaced with your own Windows login account), there exists a file “profiles.ini”. That’s a simple text file that you can examine with Notepad, or “Type” at the Windows Command prompt. Mine looked like this:



What that tells us is that the full path to the folder we care about is:


Yours will be different, of course – it won’t be “LeoN”, and that “8h1k0c0z” will probably be something else.

It’s in that folder that everything is stored. And I do mean everything.

Optional: choose your own location

Even though you don’t need to do this, I’m going to mention it because it’s what I do to keep things a little clearer on my machine.

You can change the location of the profile folder by editing profiles.ini on the destination machine before you move.

On my machine, I changed two lines:


That tells Thunderbird that my profile is stored in f:\doc\thunderbird – a folder I created on a separate drive.

Moving day

Regardless of whether you changed it to a folder of your own choosing or left it to where that first run of Thunderbird set it, we start with a simple step.

IMPORTANT: this step is performed on the destination machine, the machine you’re moving to, the machine that does not yet have your email on it.

Make sure that the profile folder on the destination machine is empty. That initial run of Thunderbird may have placed some information there that we do not need, and we don’t want to confuse subsequent steps.

Now the heavy lifting.

Copy the complete contents of the profile folder on the source machine to the profile folder of the destination machine.

It doesn’t matter how you do it; it could be over your network, using a USB thumb drive or external hard disk, or any other way you have of copying bits from one machine to another.

What does matter is this:

  • All folders and sub-folders in the profile folder are copied.
  • All files are copied.

In my case, I created a zip file of the entire profile folder contents on the source machine, copied that across my network to the destination machine, and then unzipped it in place.

Believe it or not, you’re done.

Run Thunderbird on the destination machine and you should find all of your email, contacts, extensions and whatnot have all been transferred over.

I simply pressed “Get Mail” and picked up where I’d left off.

Do this

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26 comments on “How Do I Move Thunderbird to a New Computer?”

  1. The method described implies that both machines are running the same version of Thunderbird. I think there was a change in the way TB stored its addresses going from V2 to V3 so this method might not work if widely different versions of TB were involved.

    • I’m not sure if that’s always the case, but it’s a good idea to be running the latest version of Thunderbird on both machines. It’s always a good idea to be running the latest version of your email program and browsers, and for that matter, all programs. Browsers and email programs are some of the most vulnerable programs for malware to exploit.

  2. Thunderbird is available from John Haller etal
    as a PortableThunderbird version.
    It is meant to run from a flash drive but can be installed to a convenient spot on a system HDD.

    When installed on a system HDD no registry entries are made.

    It is standalone.
    Once installed a desktop shortcut is created to the PortableThunderbird.exe.

    To move to a new machine just copy the entire folder containing Thunderbird to the new machine.

    Make a shortcut to the .exe and you are done.

    Something to consider for the future.

    Quite a few of my programs are standalone for this reason.

    I install them on a separate partition as well.

    Leo’s method should work for Thunderbird installed on a linux machine.

    The location of the profile folder in many Linux distributions is a hidden folder in
    is /home/user name/.thunderbird

  3. I do not use Thunderbird, yet, have studied the subject: Acording to the Mozilla sites you can backup and transfer with MozBackup. Does that not work?

    It may. Given the simplicity of the process I’ve outlined above I’ve never felt the need.


  4. “…using CD-ROMs or DVDs…”
    Wouldn’t using these to move the profile data change the file properties to “Read Only” and cause problems? I used that method some years back and had to remove the “Read Only” before Mozilla email was able to read the profile information.

    Yes, read-only may be added, and would need to be removed first.


  5. Actually, both FirfeFox and Thunderbird let one place its data anywhere one wants. One has to run either program from the “Run” box using the parameter -p as in
    Firefox -p
    Thunderbird -p
    This lets one place the data in an easy place instead of some folder BURIED in some directory structure whose name Microsoft changes from time to time. Click “Create Profile”, give it a name, click on “Choose Folder” . . .
    Thus, a better answer would be to run Thunderbird with the “-p” parm in the destination machine, CHOOSE where to place the stuff, then copy all the stuff from the source machine to the destination one.
    In fact, because it is difficult to “extricate” one’s personal (important) data from under “Documents and Settings” or whatever name MS chose for “Windows du jour” (since a zillion different things are saved thereunder), it’s not a bad idea to define a separate folder or drive in which to store one’s REALLY importat, personal data.

  6. Like Leo, I use Thunderbird and have for a long time. However, unlike Leo, I opt for the portable version of Thunderbird (see rather than the normally installed version – dare I say the legacy version.

    I often copy my email and it simply involves copying one folder, a folder that I named and placed. Seems the easier approach. No need to be bothered with sub-folders at all.

    Leo’s idea of keeping email in a TrueCrypt container is excellent. I do this when traveling and should do it at home too…

  7. The article has been read, but unfortunately I have a slightly different twist to this issue.
    I was wondering if you can help me with a problem with my computer system. I had to rebuild my Windows 7 Ultimate computer and I am having an issue restoring the e-mail messages from Thunderbird 7.01. I am using Mozilla Thunderbird 7.01 to read the messages from as I do not like all the advertising and side-bars that are in
    What happened is that when the re-build happened I did not know about a program called MozBackup that lets you backup all of your e-mail and addresses. After the system was rebuilt I restarted my e-mail with Thunderbird to read all of the new messages. This was done because 3 days had passed and I needed to read the new e-mail.
    After I found out about MozBackup, I re-installed the old hard drive and was able to backup all of the e-mail messages. I then re-installed the new hard drive and backed up all of the e-mail messages. I have kept all of the backup files so if the sequence needs to be changed, that can be done.
    I then restored the old e-mail messages as I needed the folders that were created. I would like to know if there is a way to combine the new e-mail messages with the old e-mail messages so they are all in one location. If I had to edit the combined list that would not be a problem. The goal is to get all of the e-mails in one location.
    If there is another way to backup the e-mail files, I can still do that as I kept the old hard drives in case there were any issues with the new install of Windows 7.
    Thanks for any help or insight that you could give for helping me with this issue.

  8. This is a great method to back up your Thunderbird emails and contacts. Follow the instructions in the article and copy them to a folder on a backup drive.

    If you do system image backups, this wouldn’t be necessary as the entire folder is Thunderbird backed up. That’s one reason Leo recommends system image backups over just copying files. Files like this might be neglected unless you know where they are all located.

  9. Hi, Leo. This is less a comment than a question arising due to my old laptop failing (my fault – I killed it via carelessness) and having to xfer everything to a new computer. I just learned (OK, I’m slow and out of touch sometimes) that Thunderbird is its own website now after Mozilla dropped it from its product line. I like it and have been using it since switching from Eudora which I had installed on my Win95 machine back in the 19th century. Still get updates and it still seems to work fine. What I’m asking is do you still use it, and still recommend it? (Ain’t broke — don’t fix?) BTW: This happened about 3 weeks or so ago, so I’m behind on TEH podcasts. I’ve really missed listening to you guys toss things around.
    Ta for now.

  10. Hello Leo Notenboom:
    My name is Aron Sayal, My email is: {removed}
    I tried zipping my profile + the .ini file as stated in your video, but the .zip ending did not come up, as I am transferring from windows7 to windows10. It is just a compressed folder on the USB drive.. Please let me know how to proceed at my email.

    Thank you,

  11. Is it possible to move Thunderbird from a Mac to a PC that is already running Thunderbird and have the data merged? I wish I’d seen your video before I installed Thunderbird on my new PC.

  12. Two questions Leo:
    1. I take it that your advice applies when transferring from Windows 10 to 11.
    2. If I’ve already installed Firefox on the new PC (and used it) should I delete the profile there and start the transfer process again. What I’ve tried so far doesn’t take – maybe that’s the reason?

    BTW, I’m sending this from my NEW PC!

  13. Hi Leo,
    My current profile.ini, below, includes the following (except comments in parenthesis) and is located under C:\users……\Thunderbird. I’d like to move the Profile data to D:\myTB_Data\Thunderbird.

    Would I be correct in guessing that I would change both IsRelative=1 lines to IsRelative=0 ??
    change both paths to: Path=D:\myTB_Data\Thunderbird ??


    Default=Profiles/5hfnb19c.default-release (10 folders and approx 40 files. The mail folder has 2 verizon pop folders (2 emails addresses) and 1 Local folder)

    Path=Profiles/3lf2l410.default (only 2 files in this folder: parent.lock and times.json) (not sure why this profile exists)



    • Yes and yes. I believe that only one profile actually holds your email (you can probably tell by timestamps on the files therein), but I don’t see a problem moving both.

      Back up first. Smile

  14. HI Leo
    Thanks a lot for the tips for moving TB emails to a new PC. I have done that near a year ago, with success using your training video.

    A terrible thingfor just happened this morning, when for the first time , TB refused to open and ask me my credentials such as : name; email adress; and password. Just after that it opened with just a few hundreds of new emails of this month. I had many thousands of emails saved in different folders in TB yestersay.

    Would you be kind enough to let me know if I lost all the missing ones or if there is a way to retrieve them.

    • Without knowing exactly what happened it’s impossible for me to say. If your computer has been getting backed up this might be a case for restoring that thunderbird folder from a backup. (Though I’d save the current one somewhere for safety as well.)


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