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Lolu chungechunge lwabekwa kunqolobane. Uyacelwa ubuze umbuzo omusha uma udinga usizo.

I updated Firefox to 15.0.1, so, why is it not opening?

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My brother and I just updated his Windows XP computer to Mozilla Firefox Version 15.0.1. After installing the update, my brother clicked on the browser, and received the message, "Firefox is already running, bot is not responding. To open a new window, you must first close the existing Firefox process, or restart your computer. Since the browser was already closed, we restarted his computer. Once booted up, he went and click the browser again, and still received the same message. So, I assumed there might have been an error in installing the update, so I uninstalled it, and reinstalled the program, and still he gets the same message. I have already browsed through the pages of the support forums, and I cannot find another person who is having the same problem. Though it is a Windows XP Operating System, is it up to date as far this older version of WIndows goes.

My brother and I just updated his Windows XP computer to Mozilla Firefox Version 15.0.1. After installing the update, my brother clicked on the browser, and received the message, "Firefox is already running, bot is not responding. To open a new window, you must first close the existing Firefox process, or restart your computer. Since the browser was already closed, we restarted his computer. Once booted up, he went and click the browser again, and still received the same message. So, I assumed there might have been an error in installing the update, so I uninstalled it, and reinstalled the program, and still he gets the same message. I have already browsed through the pages of the support forums, and I cannot find another person who is having the same problem. Though it is a Windows XP Operating System, is it up to date as far this older version of WIndows goes.

All Replies (5)

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I tried all the links that you have provided to me, and none of the solutions worked. I am still getting the same message of the browser running but not responding.

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No, that did not work either.

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Deleting the profiles.ini file should force Firefox to create a new profile.

Can you start the Profile Manager to create a new profile?


Do a clean reinstall and delete the Firefox program folder before reinstalling a fresh copy of Firefox.

Download a fresh Firefox copy and save the file to the desktop.

Uninstall your current Firefox version, if possible, to cleanup the Windows registry and settings in security software.

  • Do NOT remove personal data when you uninstall your current Firefox version, because all profile folders will be removed and you will also lose your personal data like bookmarks and passwords from profiles of other Firefox versions.

Remove the Firefox program folder before installing that newly downloaded copy of the Firefox installer.

Your bookmarks and other profile data are stored in the Firefox Profile Folder and won't be affected by an uninstall and (re)install, but make sure that "remove personal data" is NOT selected when you uninstall Firefox.

If you keep having problems then also create a new profile.