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firefox does not recreate or change prefs.js

  • 55 uphendule
  • 3 zinale nkinga
  • 5537 views
  • Igcine ukuphendulwa ngu AliceWyman

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After deleting prefs.js file Firefox does not create a new one.

Firefox does not save any of my settings so i tried all the method described in the following articles:

https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save https://support.mozilla.org/en-US/kb/how-to-fix-preferences-wont-save#w_unable-to-save-any-preferences-or-settings

finally I uninstalled FF completely, deleted the FF installation directory and moved my old profile. Reinstalling FF did not help in anyway. After reinstalling, the preferences were still not saved so I deleted the profs.js file. When I start Firefox it does not create a new profs.js file adn of course my setting are still not saved

What can i do? change? I'd rather fix this than install chrome instead...

Okulungisiwe ngu karpiyon

Isisombululo esikhethiwe

cor-el said

Can you post a screenshot that shows the content of the profile folder in details view? Did you try to remove the entire Mozilla folder in both locations to reset the entire file structure?

yes i tried removing the entire Mozilla folder in both locations after, again, uninstalling FF.

Thank you for your time - i gave up - switched to chrome.

Funda le mpendulo ngokuhambisana nalesi sihloko 👍 0

All Replies (15)

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karpiyon said

user.js Preferences Your profile folder contains a user.js file, which includes preferences that were not created by Firefox.

seek also if you have some code inside your user.js file, that blocks changes to the prefs.js file. (when firefox starts preferences you've added to the user.js file are automatically copied to the prefs.js).

The user.js file does not exist by default. If you create the file, forget it, if you have not create the file then delete the User.js file, to see if the problem goes away (some programs create and write in the file also).

thank you

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ideato said

karpiyon said
user.js Preferences Your profile folder contains a user.js file, which includes preferences that were not created by Firefox.

seek also if you have some code inside your user.js file, that blocks changes to the prefs.js file. (when firefox starts preferences you've added to the user.js file are automatically copied to the prefs.js).

The user.js file does not exist by default. If you create the file, forget it, if you have not create the file then delete the User.js file, to see if the problem goes away (some programs create and write in the file also).

thank you

Thank you, one of the things I tried, when this problem first occurred, was to use user.js file to store the settings since my profj.js was not saved. It was not a very convenient way so i deleted it. After that i reinstated FF as mentioned and carried out further steps.

I do not have users.js file anymore.

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I note you stated there is no longer a user.js file. However the Troubleshoooting information you posted suggests otherwise as it states

Your profile folder contains a user.js file, which includes preferences that were not created by Firefox.

Maybe it is worth searching recursively for user.js file and any other profiles.


Another point that may give someone some clues. What if any changes do you notice when a setting or preference is flipped. Let's try that with Hardware Acceleration (HA) a subject already mentioned several times.

  • When you turn off hardware acceleration does that appear to take effect for the current session -
  • Use menu -> Options|preferences -> |Advanced| ->|General| -> []... hardware acceleration ...
    • If you look in about:config do you see the prelsef layers.acceleration.disabled flip {it should flip in real time)
    • When disabled = true do you see this listed in your troubleshooting information|about:support {you will need to reload the page to see a change)

I suppose to be meaningful many of these tests or troubleshooting steps should be conducted in Firefox & Windows SafeMode with all plugins disabled and using an additional clean default test profile. (Specifically this test of flipping a pref should then be tried with some other pref - one Safe Mode itself does not flip)

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THANK YOU ALL for your true attempts to help me. I realized i am spending, or rather wasting too much time on this issue.

I've installed chrome and uninstalled FF.

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Can you post a screenshot that shows the content of the profile folder in details view?

Did you try to remove the entire Mozilla folder in both locations to reset the entire file structure?

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Isisombululo Esikhethiwe

cor-el said

Can you post a screenshot that shows the content of the profile folder in details view? Did you try to remove the entire Mozilla folder in both locations to reset the entire file structure?

yes i tried removing the entire Mozilla folder in both locations after, again, uninstalling FF.

Thank you for your time - i gave up - switched to chrome.

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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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moderator selected the Chosen Solution as the Owner of this thread has stated twice that he has stopped using Firefox in lieu of Chrome

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Sorry for this. I tried all i can think of before i started this thread. I was thinking of digging further using other monitor tools but i realized t would be taking too much of my time.

So again, thanks everyone who tried to help.

I am wring this via my new Chrome browser...

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To karpiyon: I see that you have given up for now and have uninstalled Firefox but here are some related bug reports in case it helps others (see Bugzilla Etiquette) Bug 495735 - Corrupt prefs.js file not removed if backup file (invalidprefs.js) exists Bug 415910 - New account creation because prefs.js disappeared Bug 393614 - SeaMonkey does not create prefs.js file if that is missing for other related "lost prefs.js" bugs seeBug 193638 - (startup) [Meta] corrupt or lost pref.js / startup configuration error (tracking bug)

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AliceWyman said

To karpiyon: I see that you have given up for now and have uninstalled Firefox but here are some related bug reports in case it helps others (see Bugzilla Etiquette) Bug 495735 - Corrupt prefs.js file not removed if backup file (invalidprefs.js) exists Bug 415910 - New account creation because prefs.js disappeared Bug 393614 - SeaMonkey does not create prefs.js file if that is missing for other related "lost prefs.js" bugs seeBug 193638 - (startup) [Meta] corrupt or lost pref.js / startup configuration error (tracking bug)

Yes I uninstalled FF and moved to chrome but i am still here... Tegarding your suggestions:

  • Corrupt prefs.js file not removed if backup file (invalidprefs.js) exists

I did not have invalidprefs.js file

  • New account creation because prefs.js disappeared

As far as i can recall no new account was ever created.

  • SeaMonkey does not create prefs.js file if that is missing

what os SeaMonkey? if this is a software which may be installed then i do not have it.

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The bugs related to "no new account" and "SeaMonkey" refer to other Mozilla applications (Thunderbird mail app, SeaMonkey Internet suite) that share the same "core" code with Firefox. They also contain a prefs,js file that saves settings . I posted those in case some of the included information might help others.

Out of curiosity, what security software do you use? I came across a number of bugs referring to PC-Cillin and prefs.js - see these results.

In any case, f you're still game, you could try installing Firefox again. Or, you could install SeaMonkey (the suite, or just the browser component) and see if you can save preference settings in that.

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Hi, I use NOD32 on win7 x64. I'd rather not install SeaMonkey since it is not what i had in the first place. I could however, re install FF but from my perspective, nothing had changed, hence what can it contribute?

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I was thinking your antivirus or another security program running in the background (or even malware) might be locking the prefs.js file or preventing changes from being saved. Nothing much came up googling "NOD32 ESET prefs.js Firefox" except for this (related to malware) and this (related to background programs preventing prefs.js changes).

Have you tried restarting the computer in Windows Safe Mode with Networking*, to prevent Startup programs from running automatically? You can reinstall Firefox in Windows Safe Mode and run it awhile, to see if you are able to save the preference changes you want to make. If you can do that, I would save a copy of prefs.js for backup, then post back.

[*] http://windows.microsoft.com/en-US/windows7/Start-your-computer-in-safe-mode


P.S. SeaMonkey also uses the prefs.js file so my thinking there was, if you don't see the same issue in SeaMonkey then something might be targeting Firefox.

Okulungisiwe ngu AliceWyman

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On possible malware:

Your extensions list in "More system details" shows this: Default Extension 1.0 (59D317DB041748fdB89B47E6F96058F3@defext)

It seems that this is the potentially malicious "Settings Protector" extension. Only thing, the google results mention Chrome, not Firefox. Anyway, I would also scan for malware using the tools suggested here:

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