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Firefox hangs when I try to open the tools --> options version 38.0.1

  • 5 iimpendulo
  • 3 inale ngxaki
  • 9 views
  • Impendulo yokugqibela ngu Scribe

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I am not sure if I have a virus or some update has firefox hanging? Within the last week something has changed so that when I try to go to tools -> options Firefox tries to open a new tab. I actually just looked up the latest updates to Firefox and it updated to 38.0.1 about 2 days ago and that is when I started having problems. At this point Firefox just hangs (Not Responding). I tried running Firefox in safe mode and it still hangs. I went into about:config and changed the browser.preferences.inContent and at first I thought that fixed it but over the past day it still crashes when I try to view the options window/tab. I can open up Yahoo and Hotmail mail sites which open new tabs so it isn't just opening a new tab. I have run Malwarebytes and Norton Anti-virus and nothing major was found.

If I type about:preferences in the address bar it also hangs. It never fully crashes so there aren't crash reports. It just hangs and says not responding. If I do control+Alt+delete is also says not responding.

Any ideas?

I am not sure if I have a virus or some update has firefox hanging? Within the last week something has changed so that when I try to go to tools -> options Firefox tries to open a new tab. I actually just looked up the latest updates to Firefox and it updated to 38.0.1 about 2 days ago and that is when I started having problems. At this point Firefox just hangs (Not Responding). I tried running Firefox in safe mode and it still hangs. I went into about:config and changed the browser.preferences.inContent and at first I thought that fixed it but over the past day it still crashes when I try to view the options window/tab. I can open up Yahoo and Hotmail mail sites which open new tabs so it isn't just opening a new tab. I have run Malwarebytes and Norton Anti-virus and nothing major was found. If I type about:preferences in the address bar it also hangs. It never fully crashes so there aren't crash reports. It just hangs and says not responding. If I do control+Alt+delete is also says not responding. Any ideas?

All Replies (5)

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I should also note that I did refresh Firefox and went through all of my programs (Windows Control Panel -> Add/Remove programs) and did not see any suspicious programs listed.

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Anyone else have this problem?

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You can check for problems with preferences.

Delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in the current Firefox release.


Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.


Do a clean reinstall and delete the Firefox program folder before (re)installing a fresh copy of the current Firefox release.

If possible uninstall your current Firefox version to cleanup the Windows registry and settings in security software.

  • Do NOT remove "personal data" when you uninstall your current Firefox version, because this will remove all profile folders and you lose personal data like bookmarks and passwords including data in profiles created by other Firefox versions.

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

  • (32 bit Windows) "C:\Program Files\Mozilla Firefox\"
  • (64 bit Windows) "C:\Program Files (x86)\Mozilla Firefox\"

Your bookmarks and other personal data are stored in the Firefox profile folder and won't be affected by an uninstall and (re)install, but make sure NOT to remove personal data when you uninstall Firefox as that will remove all Firefox profile folders and you lose your personal data.


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I actually downloaded Firefox 37.0 because up until 38.0.1 everything was working flawlessly. After installing the older version everything worked perfectly.

cor-el - Do you think it is worth troubleshooting? I assume this is a bug and maybe they figure it out in a future version?

Thanks for the help!

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Hi, Mozilla is aware of a problem affecting some users of v38, and is working to fix it in v38.0.5 - Firefox is slow after updating to Firefox 38.

If this is the cause of your issue, we are sorry for the inconvenience.

If your question is resolved by this or another answer, please take a minute to let us know. Thank you.