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Tried all the fixes for "Firefox is already running, but is not responding, " etc and am coming up blank. Do I have to just drop firefox?

Posted

Tried deleting firefox and reinstalling latest version to no avail. Tried all fixes from previous questions to no avail. Haven't seen anybody say that they've actually had a suggested fix WORK, but have seen hundreds of people with the problem.

Additional System Details

This happened

Every time Firefox opened

Installed Plug-ins

haven't installed any plugins since reinstalling latest firefox.

Application

  • User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.1; Trident/4.0; Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1) ; .NET CLR 1.1.4322; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729; InfoPath.2; .NET CLR 2.0.50727)

More Information

can't close it, can't open it, everything else already explained above.
Can't determine exactly how or when this started but within the past few months. Rebooting helped at first, but I can't go to task manager and kill firefox, and can't remove the "parent.lock" either.
Running in compatibility mode doesn't do anything either.

Chris Ilias
  • Moderator
115 solutions 1064 answers

In the extra info you provided, you said that you couldn't remove parent.lock and that you couldn't kill firefox.exe. Parent.lock cannot be deleted if firefox is running. So the issue is why can't you kill the firefox process?

Are you using something like a Firefox preloader, which is designed to keep firefox running? Other than that, try the solutions at https://support.mozilla.com/en-US/kb/Firefox%20hangs#w_hang-at-exit

Question owner

thanks chris, but I can't even access firefox now to try the "hangs at exit" solution. I guess I'm not using a "preloader," since I've never heard of it I'm pretty sure I didn't install it. I've tried all of the solutions...have you seen anyone actually say that any of these solutions worked? hahaha....sorry, several hours of trying different "fixes" is leaving me impatient. I've contacted mozilla, since I get that option now when trying unsuccessfully to even log on. thanks again, chris...howard

Chris Ilias
  • Moderator
115 solutions 1064 answers

If you restart your computer, is firefox.exe automatically loaded?

To answer your question,
Yes, solutions in the knowledge base have to have proven cases, so you know 'This solutions have worked for others.'

Question owner

No, I just powered down and up again, and firefox.exe was not loaded. I was finally able to delete "parent lock," and seem to be able to log off and on again without the error and lockout occuring. Oops, spoke too soon; problem is still there after deleting "parent lock." So now the question is, even after I kill a profile, start a new one, delete "parent lock," kill all of my applications and extensions, and kill hyperthreading, why do I still have this issue? I've wasted hours trying to keep firefox as my browser, and for the life of me I can't figure out why it just started doing this out of nowhere after using firefox for a year.

Modified by cadillac

Question owner

Ok, I believe it's operating correctly now; apparently when I deleted a profile and started a new profile, or somewhere in the mix, the add-ons and extensions all got turned on, after I had disabled all of them, intending to update them once things were working. So, it took killing hyperthreading, deleting "parent lock," turning off all extensions and add-ons, and starting a new profile then again disabling all extensions and add-ons until updated before I could use firefox, and I still don't know what actually triggered this chain of events. thanks again for the help, Chris.

Question owner

Spoke too soon; it's back to saying that firefox is already running after opening, closing and trying to reopen firefox. Don't know whether it's worth trying to go through the entire procedure again..what the heck, isn't this something that can be addressed by mozilla? sorry...a bit burned out after spending hours on this to no avail.

Question owner

After trying all of the "fixes" listed here, the only apparent working solution is to exit using "File," "exit" to close firefox, otherwise I have to kill one profile and start another just use firefox.

Chris Ilias
  • Moderator
115 solutions 1064 answers

If you have Firefox open, the parent.lock file should be there, and should not be deleted. It's only when Firefox is not running that parent.lock should not be there.

When you say that you started a new profile, I assume you mean using the profile manager (as explained in the Use the Profile Manager to create and remove Firefox profiles article). If so, and the problem remains in a brand new profile, then the cause of the problem is not in your original profile. It's probably some external program that is preventing Firefox from closing properly.

Do you have a firewall or anti-virus program running?

Question owner

Yes, I'm currently using PC Tools Spyware with antivirus. Now I can't access the Profile Manager to cancel a profile and start a new one by going to "Run" and typing "C:\Program Files]Mozilla Firefox\firefox.exe" like I could before. I'm here using IE.

David McRitchie 321 solutions 3089 answers

To properly close Firefox use File > Exit as you already determined, and that you would have seen when looking for solutions.

But your real problem I believe is in how you are attempting to run multiple profiles at the same time. You can only have one default browser and only one default profile. Any other profile must be started with -no-remote and it is parent.lock that protects this to make sure that you use only one profile at a time.

For more information start with

For more details and setup, see

Chris Ilias
  • Moderator
115 solutions 1064 answers

Maybe something in PC Tools Spyware is preventing Firefox from closing properly. As a test, try disabling it then closing Firefox. If that works, then maybe there's a setting in PC Tools Spyware that you can change.

Question owner

Chris, it does turn out that on PC Tools website, they tell you that it has conflicts with Firefox 7. I reinstalled firefox 6 and now seem to have no problem. I don't even need to worry about "properly closing out" firefox 6, just like before. I'll give you a "Solved It," since you got me so close! thanks again!!!

Question owner

to dmcritchie, I've only ever had one default browser. I am not attempting to run several profiles at once. In all the time I've been using firefox, I've never once "properly closed " firefox until this started and I did (as you noted) see that people were saying that I would have problems unless I did this. After spending many hours trying to resolve this, I'm simply going back to firefox 6 unless and until I see that Mozilla and PC Tools have again become joined at the hip. thanks!

Question owner

Alas, I spoke too soon....again. Going to firefox 6 only temporarily appeared to have worked. I'm not sure this is worth all of this...I'll probably have to use IE to keep trying to fix it, I guess...sheesh.