Why won't Firefox run/open at all, no matter how I try to start it, after having been updated to v41.0.1?
After updating to Firefox 41.0.1, yesterday, I'm not able to start or open Firefox. My operating system is Windows XP. I have not received any error messages and have no reason to think that the update was unsuccessful. I've scanned my computer several times, and have no reason to think that I have any viruses/malware/etc.. All other browsers function normally, and my computer has no other symptoms that I have noticed.
A window saying that Firefox would be updated after restarting it or after the next time I opened it, and I shortly thereafter turned off my computer. When I turned it back on and tried to start Firefox, nothing happened. I have tried to open it via Run..., by clicking on the desktop shortcut, by going into the Firefox folder and trying to start it from there, and every other way that has been suggested by various pages here. Nothing works. No matter what I do, the Task Manager never shows that firefox.exe is running. As a result of this, I've not been able to try any suggested solutions that rely upon my being able to use Firefox in any way. I have, however, tried every other suggestion. Nothing has worked. I can't even use the Profile Manager; when I try, nothing happens. As most pages sternly warn me that reinstalling or downgrading Firefox will either do nothing or be dangerous, I have no idea what else to try. I guess, at this point, that that probably means I'm missing something obvious, but I still don't have any idea what I could be missing.
Thank you in advance very much for your help! It's GREATLY appreciated.
Chosen solution
Hi, have a look at this first - Firefox won't start - find solutions, but if nothing there helps, it may be that this can be solved by performing a Clean reinstall. This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.
To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.
- Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
- After the download finishes, close all Firefox windows (or open the Firefox menu
and click the close button 
).
- Delete the Firefox installation folder, which is located in one of these locations, by default:
- Windows:
- C:\Program Files\Mozilla Firefox
- C:\Program Files (x86)\Mozilla Firefox
- Mac: Delete Firefox from the Applications folder.
- Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
- Windows:
- Now, go ahead and reinstall Firefox:
- Double-click the downloaded installation file and go through the steps of the installation wizard.
- Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.
More information about reinstalling Firefox can be found here.
WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.
Please report back to say if this helped you!
Thank you.
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Chosen Solution
Hi, have a look at this first - Firefox won't start - find solutions, but if nothing there helps, it may be that this can be solved by performing a Clean reinstall. This means you remove your Firefox program files and then reinstall Firefox. This process does not remove your Firefox profile data (such as bookmarks and passwords), since that information is stored in a different location.
To do a clean reinstall of Firefox, please follow these steps: Note: You might want to print these steps or view them in another browser.
- Download the latest Desktop version of Firefox from mozilla.org (or choose the download for your operating system and language from this page) and save the setup file to your computer.
- After the download finishes, close all Firefox windows (or open the Firefox menu and click the close button ).
- Delete the Firefox installation folder, which is located in one of these locations, by default:
- Windows:
- C:\Program Files\Mozilla Firefox
- C:\Program Files (x86)\Mozilla Firefox
- Mac: Delete Firefox from the Applications folder.
- Linux: If you installed Firefox with the distro-based package manager, you should use the same way to uninstall it - see Install Firefox on Linux. If you downloaded and installed the binary package from the Firefox download page, simply remove the folder firefox in your home directory.
- Windows:
- Now, go ahead and reinstall Firefox:
- Double-click the downloaded installation file and go through the steps of the installation wizard.
- Once the wizard is finished, choose to directly open Firefox after clicking the Finish button.
More information about reinstalling Firefox can be found here.
WARNING: Do not use a third party uninstaller as part of this process. Doing so could permanently delete your Firefox profile data, including but not limited to, extensions, cache, cookies, bookmarks, personal settings and saved passwords. These cannot be easily recovered unless they have been backed up to an external device! See Back up and restore information in Firefox profiles.
Please report back to say if this helped you!
Thank you.
I had another look through the "Firefox won't start" page, but those suggestions still didn't work. The Clean reinstall, however, did! Perfectly, too. Bookmarks, passwords, add-ons...everything's still there, just as I left it. Thank you so much for your help. I'm incredibly grateful.
My only remaining question probably isn't that important in the grand scheme of things, but I'm still curious--what might have caused this issue, in the first place? I ask only because, if possible, I'd very much like to avoid whatever the problem was, in the future.
Again, thank you very, very, very much.