Mozilla Firefox®, Portable Edition is the popular Mozilla Firefox web browser bundled with a PortableApps.com 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.
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.
Related Posts
- Register Firefox Portable With Default Programs in Windows 7/Vista
- Internet Explorer Extension to Open Current Web Page Using a Different Browser
- Restore Missing “Mozilla Firefox” Entry to Set Program Access and Defaults in Windows XP
- Open in RegEdit Add-on for Mozilla Firefox
- Fix for Windows Error Opening Internet Shortcut or Local HTML File Using Firefox
If you enjoyed this post, make sure you subscribe to our RSS feed! We feature Tips, Troubleshooting information, Scripts and Utilities for Microsoft Windows Operating Systems!
Prefer an E-mail subscription?





Why not make an autorun binary that registers Mozilla Portable as a default browser?
i also have an issue a few have raised here already, but there’s still no resolution to it… after following the listed steps to make firefox portable the default browser, it now works fine if and only if it’s not running. that is, if one clicks on a link while firefox portable is not running, it starts and loads the clicked link as one would expect, but if firefox portable is already running, then you get the message “firefox is already running but is not responding. to open a new window you must first close” instead of simply opening a new tab for the clicked link. any help would be appreciated.
Thanks! That worked perfectly.
My system became very messed up after having Firefox full install then a /Firefoxportable and then switching to/Firefox folder due to wanting to make the profile correctly integrated into the portable from the full.
It kept wanting to create a new profile in “C:\. . .\Application Data” every time I clicked on a link in another program. Ten seconds with this little download and everything is working perfectly again.
Thanks! Much appreciated!
Works nicely for me (XP SP3). One issue it doesn’t fix is opening PDF links with the default browser, not IE. (I’m still using Adobe Reader 6, no need to change it)
1-) If I running only one instance of firefox portable, how do I to open a webpage in a new tab? (Avoid Firefox is running… message)
2-) Windows Live Messenger still opens pages in IE…
What happens when you unplug the USB which has Portable Firefox? Does it switch back to the earlier browser?
yes!!
thanks to developer
Worked for me just fine with Firefox Portable and XP. I am not using FF from a USB drive though so not sure if that might be the difference?
Not working for me either. Running google desktop and asking it for an index status still tries to open IE.
this is excellent, but it doesn’t seem to be working on portable firefox / xp. any suggestions? it still goes back to IE every time…