Mozilla Profiles

The aim of this page is to document all the information on Mozilla Profiles that I have.

Firefox and Thunderbird

There is, of course, a lot of common ground between Firefox and Thunderbird, especially around profiles, so let's deal with the common stuff. To see what is going on with profiles the "easy" way to get profile information is via the "hamburger" menu, from where you can select Help and then "Troubleshooting Information", this opens a page where you can click "about:profiles".

The about:profiles page will give you all the profile information you need. Typically it will show you a single, default profile that has two directories, a "Root Directory" and a "Local Directory", these will both be located in an area of your drive that is for user specific information, whether on Mac or PC. Here you can create new profiles, and these will also have two directories. However, if when creating your profile, you choose another directory, say on Windows that might be "D:\Mozilla\Firefox\MyProfile", then you will find that single directory, labelled "Root Directory", is in fact the other two merged together.

When I wanted to save space on my C drive, I decided to move my Firefox profile to my D drive, this is what I did:

  • In Windows Explorer I created a new directory, on the D drive for my Firefox profile
  • Open about:profiles in Firefox and click "Create a New Profile"
  • I followed the wizard and chose to put it in the directory I just created
  • Firefox always makes new profiles the new default profile
  • My original, "default" profile had two "Open Folder" buttons, so I clicked both of these to open Windows Explorer in these two locations
  • Then I closed Firefox
  • Using Windows Explorer I copied the contents of both old profile directories to the new single directory
  • Launch Firefox and it will be running off the new profile
This is, not quite as slick as it might be, however it does work and is the same for both products.

There are a good number of useful pages on this subject, here are some:


Many is the occasion where I have moved a profile from one computer to another. The steps are as follows:

  • Load Thunderbird on the old/current computer
  • Select "Troubleshooting Information" from the Help menu
  • In the "Application Basics" section at the top, click the "Show Folder" button
  • Close Thunderbird but leave Windows Explorer running
  • Then in Windows Explorer take the contents of the folder and copy them to a network share or USB drive
  • Install Thunderbird on the new computer
  • On the new computer open "Troubleshooting Information" and click the "Show Folder" button as before
  • Leave Windows Explorer open at the profile directory but close Thunderbird
  • Delete everything in the profile directory
  • Copy the old profile directory from the network share or USB drive
  • Launch Thunderbird and everything should work as before
Clearly this works best where you have the exact same version of Thunderbird to minimise the risk of problems.

If you simply want to move the profile from one location to another, to make backup easier for example, then take a look at Moving your profile folder - Thunderbird - MozillaZine Knowledge Base. I have done this myself and chose the modifying the profile.ini file technique, which worked fine.