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Can't stop Firefox from running

  • 6 replies
  • 1 has this problem
  • 6 views
  • Last reply by FredMcD

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I tried starting the Firefox browser multiple times by clicking both the shortcut icon and the file. After nothing happened, i opened the task manager and stopped the browser's process(What even causes this to happen?), but when i tried to start the browser again, it just did the same thing: it started a process on the task manager, but it didn't start. No matter how many times i stopped the process, the same thing would happen. I tried creating a new profile, and it worked, but i wanted to test it by closing it and opening it again, and it didn't work. Then i tried creating a third profile, but for some reason it didn't work that time, and even if it did, it'd be pretty annoying to have to create a new profile everytime i wanted to use the internet. I use Windows 10, if it makes any difference. Sorry for the long text and bad english.

I tried starting the Firefox browser multiple times by clicking both the shortcut icon and the file. After nothing happened, i opened the task manager and stopped the browser's process(What even causes this to happen?), but when i tried to start the browser again, it just did the same thing: it started a process on the task manager, but it didn't start. No matter how many times i stopped the process, the same thing would happen. I tried creating a new profile, and it worked, but i wanted to test it by closing it and opening it again, and it didn't work. Then i tried creating a third profile, but for some reason it didn't work that time, and even if it did, it'd be pretty annoying to have to create a new profile everytime i wanted to use the internet. I use Windows 10, if it makes any difference. Sorry for the long text and bad english.

Chosen solution

I solved the problem. Apparently there was a thing called XPCOM that was deleted for some reason. I reinstalled it and it's working fine, at least for now. Anyways thank you guys for caring.

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All Replies (6)

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Your English is fine. There are several things that could cause your problem.

Some problems occur 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}


Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

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FredMcD said

Your English is fine. There are several things that could cause your problem. Some problems occur 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}

Start Firefox in Safe Mode {web link} by holding down the <Shift> (Mac=Options) key, and then starting Firefox.

A small dialog should appear. Click Start In Safe Mode (not Refresh). Is the problem still there?

Thanks for the time, but this is not my problem. Firefox is connecting to the internet just fine, but i just can't open it. It's a problem like described here except i do what the tutorial says and it just keeps happening, which is weird because it worked the last time i head this problem. Also, i tried to follow the tutorial that you linked, but i can't find Firefox.exe.

Modified by problem7

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There are some security programs that may stall Firefox part of the way through its launch. I think one of them might be older versions of Websense, however others may cause this issue from time to time.

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Make sure all such programs are checked for updates.

Start your Computer in safe mode with network support. Then start Firefox. Try Safe websites. Is the problem still there?

http://encyclopedia2.thefreedictionary.com/Linux+Safe+Mode Starting Any Computer In Safe Mode; Free Online Encyclopedia

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Chosen Solution

I solved the problem. Apparently there was a thing called XPCOM that was deleted for some reason. I reinstalled it and it's working fine, at least for now. Anyways thank you guys for caring.

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That was very good work. Well done. Please flag your last post as Solved Problem so others will know.