How to set Firefox Portable as the default browser in Windows XP


Mozilla Firefox®, Portable Edition is the popular Mozilla Firefox web browser bundled with a Launcher as a portable app, so you can take your bookmarks, extensions and saved passwords with you. Mozilla Firefox Portable Edition can be copied to a thumb drive so that you can use it where ever you go. Mozilla Firefox®, Portable Edition does not register itself with the system, and thus cannot be set as the default browser using the GUI.

For Windows Vista and higher: To set Mozilla Firefox Portable Edition as your default browser in Windows Vista, Windows 7, Windows 8 or Windows 10, see article Register Firefox Portable with Default Programs in Windows instead.

DefaultBrowser, an utility which I wrote allows you set the default web browser for your user profile in Windows XP, without affecting other users in the system. DefaultBrowser  v1.7 (and higher) supports Mozilla Firefox®, Portable Edition. Here is how to set Mozilla Firefox®, Portable Edition as the default browser for your user profile in Windows XP.

Visit the DefaultBrowser page, download the application and save the file to Desktop. Unzip the file and extract the contents to a folder of your choice say D:\Software\Browsers.

Select Firefox Portable from the list of browsers, and click Apply.

In the Browse dialog box, select the location where the executable FirefoxPortable.exe is located.

Mozilla Firefox®, Portable Edition is now set as the default browser for your user account.

Important: If you’re using Mozilla Firefox Portable Edition from a USB disk, whenever the drive-letter for the USB disk changes, you’ll need to re-register FirefoxPortable.exe using the DefaultBrowser utility again. For instance, the drive-letter for your USB disk may change when adding additional hardware in your system.


About the author

Ramesh Srinivasan founded back in 2005. He is passionate about Microsoft technologies and has a vast experience in Windows — delivering support for Microsoft's consumer products. He has been a Microsoft MVP (2003-2012) who contributes to various Windows support forums.

9 thoughts on “How to set Firefox Portable as the default browser in Windows XP”

  1. .mht files does not open with Firefox Portable?

    and i found ,i run regedit ,edit like this


    and then ,is ok…
    now i can open .mht files with firefox portable.

    i wish you can update your soft.

  2. Tried it. Downloaded it from different site. Tried again. Didn’t work anytime it was used. Explorer remained default web program. Didn’t like it.

  3. @hazen:
    your suggestion to made .MHT files readable by Firefox did sound quite weird to me as MHT is a Microsoft proprietary format. In fact I could not catch how changing Registry in a so simple way would change Firefox so much. But I gave it a try and nothing happened as I had presumed: Firefox remains unable to open MHT files without a right extension/plug-in installed.

    To make possible reading and even writing of MHT files, there are at least two extensions: the oldest one, that did not to work at the times of FF2, I mean MAF (Mozilla Archive Format) and maybe the most popular, UnMHT that can read and write MHT files and even convert HTML files and associated image folders in a snap. Great integration in Firefox Portable 5!

    Cheers from France

  4. Did that and when firefox is closed it works, but when it’s already open, i get the “firefox is already running but is not responding…” error message instead of it just opening a new tab.

  5. I tried the one from autohotkey and i still get the same results.
    When FFPortable is closed it works but when it is already opened i get the error message.
    Why can’t it just open a new tab?

Comments are closed.