I use Mozilla’s Thunderbird e-mail client, and their Firefox web browser. Every now and then, I would need to transfer all my settings from one computer to another, or from one OS install to another. Recently, I was once again faced with this little problem.

In Thunderbird, I used to copy the Mail folder over, the prefs.js file, and some other odds and ends – but that meant I had to reinstall all my extensions and everything. The same was true for Firefox – minus the Mail folder.

So, the other day, I finally figured out how to transfer ALL the settings over in one ridiculously, stupidly easy step. Why I was unable to find any information about this on the web before is beyond me. Everything I’ve found says to copy files from inside your profile directory as I have been doing, which is entirely unnecessary.

Read on to see how to do it…

The first thing you need to do is find your profile directory. Before you can do this, you’ll probably have to go into Explorer and change the settings so that “Show Hidden Files/Folders” is checked.

In XP, do: Tools -> Folder Options.
In Vista/Windows 7, do: Organize -> Folder and search options.
In Linux/Unix, you’re on your own!

Then, find your profile as follows:

Windows XP:

Thunderbird: C:\Documents and Settings\YOUR_USER_NAME\Application Data\Thunderbird
Firefox: C:\Documents and Settings\YOUR_USER_NAME\Application Data\Mozilla\Firefox

Windows Vista / Windows 7:

Thunderbird: C:\Users\YOUR_USER_NAME\AppData\Roaming\Thunderbird
Firefox: C:\Users\YOUR_USER_NAME\AppData\Roaming\Mozilla\Firefox

So, here’s what you do:

1. Make a copy of all the contents in the appropriate directory listed above on your current system
2. Install Thunderbird and/or Firefox on your new system
3. Copy the contents from Step #1 your into the same location on your new system

That’s it. You’re done.

This will transfer everything, including bookmarks, the Mail folder, server settings, and even Add-ons.

The only problem I have encountered is that my US English dictionary for spellchecking in Thunderbird didn’t get transferred, but I’m guessing that’s because it was stored in another directory since I use the US English version of Thunderbird.

Other than that, everything just works. All my tabs in Firefox were there as I had left them before upgrading my OS, all my add-ons were there, all my e-mail — EVERYTHING.

Now, what I really want to know is why Mozilla doesn’t just give us a simple “Export/Import” option that will take the appropriate directory, ZIP it up, and stick it in a file that is handled by the same application when it is opened on the new system.

In the meantime, export/import to your heart’s content!