From MozillaZine Knowledge Base

When you create multiple profiles for Firefox, Thunderbird or SeaMonkey 2, the last selected profile is automatically used, unless you uncheck the "Don't ask at startup" option in the Profile Manager. If you want to bypass the Profile Manager and choose a different profile to start your Mozilla application, one way to do that is by using the -P "<profile name>" command line option but this will only work for profiles listed in the Profile Manager. See the Shortcut to a specific profile article for more information.

This article explains how to start Firefox, Thunderbird, or SeaMonkey 2 with any profile, including a profile that isn't listed in the Profile Manager, using the -profile "<path>" command line argument.

Background

You can use the -profile "<path>" command line argument to start Firefox, Thunderbird, or SeaMonkey 2 with any specified profile, whether or not the profile is listed in the Profile Manager. This can be useful when recovering a profile that is missing from the Profile Manager, which could happen if the profiles.ini file was deleted or incorrectly edited. You can also try out a profile you've copied to a new location or test a profile backup before adding it to the Profile Manager in this way (see Moving your profile folder for details on that process).

Caution! Be careful when entering the path to a profile. Due to the fix for bug 531532, entering a <path> to a folder that does not exist will no longer produce an error message. Instead, a new profile folder will be created at that location and the profile will be launched.

Desktop shortcut

The following explains how to create a desktop shortcut to start your Mozilla application with any profile, whether or not it's listed in the Profile Manager.

On Windows

Create a new Windows desktop shortcut to your Mozilla application (or copy an existing shortcut). Using Firefox and a profile folder named "MyProfile" as an example, right-click and rename the new shortcut "Firefox MyProfile" , then right-click the shortcut again and select "Properties", go to the "Shortcut" tab, add a space to the end of the path in the "Target" box, then add -profile, another space, followed by the path to the profile folder enclosed in quotes. For example, using a custom profile folder path of C:\Firefox\Profiles\MyProfile with a default Firefox installation directory, the Target box will show:
On 32-bit Windows:

"C:\Program Files\Mozilla Firefox\firefox.exe" -profile "C:\Firefox\Profiles\MyProfile"

On 64-bit Windows:

"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -profile "C:\Firefox\Profiles\MyProfile"

Note: For profiles listed in the Profile Manager, you can use -P "<profile name>" instead of -profile "<path>". See Shortcut to a specific profile for details.

Command line

The following examples use a Firefox profile folder but the same applies to a SeaMonkey profile folder and a Thunderbird profile folder, with the appropriate changes to the program name and profile path.

On Windows

Click the Windows "Start" button and select "Run" then type the following in the "Open:" field, then click 'OK" (press "Windows key + R" to open the Run box on Windows 7/Vista):

• To start Firefox using the profile of your choice (listed or not in the Profile Manager) use firefox.exe -profile "<path>", where "<path>" is the path to the Firefox profile folder.

For example, on Windows XP with a profile path C:\Documents and Settings\<user>\Application Data\Mozilla\Firefox\Profiles\xxxxxxxx.default (where <user> is your Windows log-in user account name) you would enter the following:

firefox.exe -profile "C:\Documents and Settings\<user>\Application Data\Mozilla\Firefox\Profiles\xxxxxxxx.default"

• To open a profile listed in the Profile Manager, use firefox.exe -P "<profile name>" (you only need quotation marks for profiles with spaces in the name)

For example, on Windows, to open a profile listed as test in the Profile Manager, use

firefox.exe -P test

On Linux

The same applies, with the appropriate changes. To open the "Run" dialog, the usual keystroke combo is Alt+F2 (it might depend on your window manager). Or you could type the same command-line at any shell prompt in a console terminal running under X11 (xterm, konsole, gnome-terminal, etc.).

To open a profile of your choice:

• ~/myprofile (listed or not in the Profile Manager):

firefox -profile ~/myprofile

• The profile listed as test in the Profile Manager (and whose path is usually ~/.mozilla/firefox/xxxxxxxx.test where xxxxxxxxx is some pseudorandom string):

firefox -P test

Creating a profile that is not listed in the Profile Manager

You can use -profile "<path>" to create a new "unlisted" profile at a given location, without starting the Profile Manager. This can be useful for troubleshooting. You should first create a new "empty" folder for the new profile. You would then use a desktop shortcut or the command line, as explained above, to specify the path to the newly-created folder. The profile data for the new profile will be stored in that folder but the profile will not be listed in the Profile Manager or in the profiles.ini file.

Again, be careful when entering the path to your new profile. Entering a <path> to a folder that does not exist will no longer produce an error message. Instead, a new profile folder will be created at that location and the profile will be launched.

See also

• Shortcut to a specific profile
• Command line arguments
• Command line arguments - Thunderbird
• Using multiple profiles - Firefox