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Firefox will not open up in Windows 7.

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  • 11 have this problem
  • 2 views
  • Last reply by guigs

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Firefox has stopped working in my computer. I have uninstalled and reinstalled 3 times now, and it will not load up. Many articles online instruct me to clean cookies, etc. but I cannot do anything if the program doesn't load. It does not even show as loaded in my Windows Task Manager. Please advise.

Firefox has stopped working in my computer. I have uninstalled and reinstalled 3 times now, and it will not load up. Many articles online instruct me to clean cookies, etc. but I cannot do anything if the program doesn't load. It does not even show as loaded in my Windows Task Manager. Please advise.

Chosen solution

Well, Firefox is up and running again! What I did was uninstall Chrome! I uninstalled FFox as well and then rebooted the computer. Before installing Chrome again, I have downloaded FFox and she is up and purring! I reinstalled Chrome and have not had any issues thus far (and never did before). The only reason I decided to uninstall chrome was because of the error message I received when I typed the prompt into cmd as suggested by @guigs2. Thanks again and happy surfing!

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All Replies (14)

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Are there any messages when you call Firefox?


Start Firefox in Safe Mode by holding down the <Shift(Mac Options)> key, and then starting Firefox. Is the problem still there?


Start your Computer in safe mode. Then start Firefox. Try Safe web sites.

Starting The Computer In Safe Mode; Free Online Encyclopedia

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I was able to start firefox only when I started my computer in safe mode. It will not open up when I hold shift+ firefox icon. Once I open firefox in computer safe mode, what do I do then to ensure it opens in normal mode? Thanks!

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Then something on your computer is blocking Firefox.

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Some problems occurs when your Internet security program was set to trust the previous version of Firefox, but no longer recognizes your updated version as trusted. Now how to fix the problem: To allow Firefox to connect to the Internet again;

  • Make sure your Internet security software is up-to-date (i.e. you are running the latest version).
  • Remove Firefox from your program's list of trusted or recognized programs. For detailed instructions, see

Configure firewalls so that Firefox can access the Internet. {web link}

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Also, check the programs that are on your computer

Windows: Start > Control Panel > Uninstall Programs. Mac: Open the "Applications" folder. Linux: Check your user manual.

Go thru the list. If you find something that you don't know what it is, use a web search.

Troubleshoot Firefox Issues Caused By Malware {web link}

Modified by FredMcD

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I disabled the firewall altogether and Firefox still does not launch. I restarted the computer in safe mode (because Firefox does launch in safe mode) and disabled all add ins. Still does not work. I have used CCleaner, Advanced System Care 7, and SuperAntiSpyware in addition to McAfee to scan and remove spyware and malaware. Hmmm....

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I called for more help on this. I would like you to try more thing. I want you to disable all of your protection programs for just a minute. Then try Firefox normally. If you are concerned, unplug / turn off the modem.

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Is it possible to open Firefox with the profile folder?

  1. From the start menu please type:

cmd.exe

  1. hit enter
  2. Copy this below and paste it into the black window with the cursor:

"C:\Program Files (x86)\Mozilla Firefox\firefox.exe" -p

  1. The profile manager should pop up
  2. Create a new profile, any luck?

Modified by guigs

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Thanks for the input @guigs2. I did as you instructed and received this message: XML Parsing Error: undefined entity Location: chrome://mozapps/content/profile/profileSelection.xul Line Number 18, Column 1:<dialog ^="" <="" p=""></dialog>

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Chosen Solution

Well, Firefox is up and running again! What I did was uninstall Chrome! I uninstalled FFox as well and then rebooted the computer. Before installing Chrome again, I have downloaded FFox and she is up and purring! I reinstalled Chrome and have not had any issues thus far (and never did before). The only reason I decided to uninstall chrome was because of the error message I received when I typed the prompt into cmd as suggested by @guigs2. Thanks again and happy surfing!

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That was very good work on your part, Well Done !

Please flag your last post as Solved Problem so other will know.

guigs2 Has this come up before?

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Wild4hummies yes, great!

The XML parsing error suggests that something with in the program became corrupt.

That particular file: chrome://mozapps/content/profile/profileSelection.xul I did find one reference to it in the code here: http://dxr.mozilla.org/mozilla-centra.../nsAppRunner.cpp

And what is happening in that line is that its calling the profile manager, and that there is an error in that line of the code or in the profile I am not entirely sure.

If you are interested you can read the code by putting this in the url: view-source:chrome://mozapps/content/profile/profileSelection.xul

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Firefox is not working again. It worked while I unistalled Chrome, but Chrome is installed again. What in Chrome could be causing FFox not to open?

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Firefox uses the "chrome://" protocol to access its own internal files and also access files from extensions, so that has nothing to do with Google Chrome.

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Thanks for the feedback @cor-el. Any suggestions?

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If you download the install stub for the most recent version of Firefox is will install over the existing profiles. Please try this, but make a back up of your profile first:Back up and restore information in Firefox profiles