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firefox does not recreate or change prefs.js

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  • 3 have this problem
  • 151 views
  • Last reply by 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...

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...

Modified by karpiyon

Chosen solution

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.

Read this answer in context 👍 0

All Replies (20)

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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.

If you keep having problems then also create a new profile.


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1st thanks for your time!

I've already done all you suggested: >I uninstalled FF. >Deleted "C:\Program Files (x86)\Mozilla Firefox\" >moved the entire profile folder to a new location in order to save those setting for later. >run a registry cleaning program >Re install FF

>tried to change the setting setting were not saved! prefs.js is never accessed - i checked it using procMonitor as suggested earlier. Is there a hidden log file which can help me understand what is going on here? Is there a debug mode i can run?

thank you!

I did all this before i started these support thread. The only minor differences from your suggestion is that

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Hello,

just a thought......if the renamed (to prefs_OLD.js) prefs.js file is corrupted and the cause of the problem, try to move it outside of the profile folder(keep it somewhere safe),and check it again.

Another option is to create the prefs.js, it is a plain-text file like user.js file.

just thoughts ( i never create a prefs.js file myself)

thank you

Modified by ideato

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ideato said

Hello, just a thought......if the renamed (to prefs_OLD.js) prefs.js file is corrupted and the cause of the problem, try to move it outside of the profile folder(keep it somewhere safe),and check it again. Another option is to create the prefs.js, it is a plain-text file like user.js file. just thoughts ( i never create a prefs.js file myself) thank you

Thank you for your try... FF, as far as i understand it does not pay any attention to prefs_OLD.js but i already tried some more drastic ways. Ire installed a fresh copy of FF after removing my entire profile and deleting the FF installation folder. This did create a new profs.js file but this file was never changed with new settings. I then deleted this file completely from the profile folder and FF never recreated it.

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Please do this. Open the file browser / explorer on your computer. Enter this in the address bar;

Windows: %AppData%\Mozilla\Firefox\ C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\ http://kb.mozillazine.org/Profile_folder_-_Firefox#Windows Linux: ~/.mozilla/ http://kb.mozillazine.org/Profile_folder_-_Firefox#Linux Mac: ~/Library/Application Support/ http://kb.mozillazine.org/Profile_folder_-_Firefox#Mac

Using a test program, open profiles.ini and copy it's contents. Now paste it here.

Modified by FredMcD

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FredMcD said

Please do this. Open the file browser / explorer on your computer. Enter this in the address bar; Windows: %AppData%\Mozilla\Firefox\ C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\ http://kb.mozillazine.org/Profile_folder_-_Firefox#Windows Linux: ~/.mozilla/ http://kb.mozillazine.org/Profile_folder_-_Firefox#Linux Mac: ~/Library/Application Support/ http://kb.mozillazine.org/Profile_folder_-_Firefox#Mac Using a test program, open profiles.ini and copy it's contents. Now paste it here.

This is the content:

[General] StartWithLastProfile=1

[Profile0] Name=default IsRelative=1 Path=Profiles/vwk2jsmu.default Default=1

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karpiyon said

cor-el said
Does that utility show that Firefox tries to create or at least access the prefs.js file?

no

Hi - an update. I compared to reports of processmonitor, on 2 computers. In both cases i deleted the prefs.js file and wanted to see if it is written. On my "bad" computer there is one access to prefs.js which fails. On the "good" computer there are several, the first ones fail and then the file is created.

So it appears that in the "bad" one FF does not try to recreate the file for some reason.

the image with the signal line is the bad one.

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is there any possibility you are not examining the active profile ? If not already done it may be a good idea to check which profile is in use.

  • Probably expected to be /vwk2jsmu.default
  • Check by using
    Menu Button -> Help -> Troubleshooting Information -> [Open Containing folder] {wording not exact
  • Look for existing profiles, they should all contain places.sqlite search for that file.

I would have thought if Firefox somehow had no prefs.js it would have no user set prefs. So when you look at modified preferences, in troubleshooting information is that list empty.

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John99 said

is there any possibility you are not examining the active profile ? If not already done it may be a good idea to check which profile is in use.
  • Probably expected to be /vwk2jsmu.default
  • Check by using
    Menu Button -> Help -> Troubleshooting Information -> [Open Containing folder] {wording not exact
  • Look for existing profiles, they should all contain places.sqlite search for that file.
I would have thought if Firefox somehow had no prefs.js it would have no user set prefs. So when you look at modified preferences, in troubleshooting information is that list empty.

i have only one profile and it is the one FF is pointing to...

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any other suggestions?

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Do you have an Invalidprefs.js file also ? If you have it, delete the file.

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ideato said

Do you have an Invalidprefs.js file also ? If you have it, delete the file.

i do not have this file

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ideato said

Another option is to create the prefs.js, it is a plain-text file like user.js file. thank you

Try to create the file and save it in your profile folder, you can create the file definitely, but the question is if that works or not.

thanks again

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ideato said

Do you have an Invalidprefs.js file also ? If you have it, delete the file.

Don't you mean; Invalid prefs.js file ?

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Start Firefox in Safe Mode {web link} While you are in safe mode;

Type about:preferences#advanced<Enter> in the address bar.

Under Advanced, Select General. Look for and turn off Use Hardware Acceleration.

Poke around safe web sites. Are there any problems?


Separate Issue; Update your Flash Player v16.0.0.235 https://www.adobe.com/products/flashplayer/distribution3.html Shockwave Director v12.1.5.155 http://get.adobe.com/shockwave/

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karpiyon said

John99 said
<snip> I would have thought if Firefox somehow had no prefs.js it would have no user set prefs. So when you look at modified preferences, in troubleshooting information is that list empty.

i have only one profile and it is the one FF is pointing to...

Did you look at troubleshooting information ? What did you see ? Can you provide a screenshot of that and the modified prefs ?

It would be interesting to see

  • If that changes after manually creating a prefs.js file.
  • How that appears in a new clean profile. (IIRC you say newprofilesdo have a prefs.js file)
    • And what the content is of the clean profile's prefs.js file
    • And how & if the troubleshooting information changes after the prefs.js is deleted & Firefox restarted.

I do not recall seeing anyone report this problem previously


P.S. Firefox does have debuging tools. It even has some abilities with remote debugging. Although I personally have not tried any of the remote debugging options. I will not be able to help with any of this, and I do not think it it is even relevant. You are having issues before the browser is even running. So I guess sysinternals tools are the ones to use. However as background info I will provide a couple of links

Whilst I would be none the wiser, it crosses my mind that running the profiler whilst the trouble shooting page was being opened may prove some clues as to what is happening, because that page must be getting those modified prefs from somewhere, normally the prefs.js

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FredMcD said

Start Firefox in Safe Mode {web link} While you are in safe mode; Type about:preferences#advanced<Enter> in the address bar. Under Advanced, Select General. Look for and turn off Use Hardware Acceleration. Poke around safe web sites. Are there any problems?

Separate Issue; Update your Flash Player v16.0.0.235 https://www.adobe.com/products/flashplayer/distribution3.html Shockwave Director v12.1.5.155 http://get.adobe.com/shockwave/

Thank you. I did as you suggested. I can work with FF just like i do when i start it in normal mode. I change the settings for the Hardware acceleration detected no change. I modified a few other settings but just like before, when i close FF and restart it all those setting are gone - they are never saved.

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John99 said

karpiyon said
John99 said
<snip> I would have thought if Firefox somehow had no prefs.js it would have no user set prefs. So when you look at modified preferences, in troubleshooting information is that list empty.

i have only one profile and it is the one FF is pointing to...

Did you look at troubleshooting information ? What did you see ? Can you provide a screenshot of that and the modified prefs ?

It would be interesting to see

  • If that changes after manually creating a prefs.js file.
  • How that appears in a new clean profile. (IIRC you say newprofilesdo have a prefs.js file)
    • And what the content is of the clean profile's prefs.js file
    • And how & if the troubleshooting information changes after the prefs.js is deleted & Firefox restarted.

I do not recall seeing anyone report this problem previously


P.S. Firefox does have debuging tools. It even has some abilities with remote debugging. Although I personally have not tried any of the remote debugging options. I will not be able to help with any of this, and I do not think it it is even relevant. You are having issues before the browser is even running. So I guess sysinternals tools are the ones to use. However as background info I will provide a couple of links

Whilst I would be none the wiser, it crosses my mind that running the profiler whilst the trouble shooting page was being opened may prove some clues as to what is happening, because that page must be getting those modified prefs from somewhere, normally the prefs.js

Hi and thank you.

I created a new profs.js file and placed it under the profile folder. FF never changes this file when I start it or when i change settings.

I've attached the report of the troubleshooting information below:

Troubleshooting Information Application Basics Name Firefox Version 34.0.5 Update History Show Update History User Agent Mozilla/5.0 (Windows NT 6.1; WOW64; rv:34.0) Gecko/20100101 Firefox/34.0 Profile Folder Show Folder Enabled Plugins about:plugins

Build Configuration about:buildconfig

Memory Use about:memory

Multiprocess Windows 0/1 Crash Reports for the Last 3 Days Report ID Submitted All Crash Reports This application has not been configured to display crash reports. Extensions Name Version Enabled ID Adobe Acrobat - Create PDF 2.0 false web2pdfextension@web2pdf.adobedotcom

Default Extension 1.0 false 59D317DB041748fdB89B47E6F96058F3@defext HP Smart Web Printing 4.5 false smartwebprinting@hp.com

Troubleshooter 1.1a false troubleshooter@mozilla.org

Graphics Adapter Description AMD Radeon HD 5800 Series Adapter Drivers aticfx64 aticfx64 aticfx64 aticfx32 aticfx32 aticfx32 atiumd64 atidxx64 atidxx64 atiumdag atidxx32 atidxx32 atiumdva atiumd6a atitmm64 Adapter RAM 1024 Device ID 0x6899 Direct2D Enabled true DirectWrite Enabled true (6.2.9200.16571) Driver Date 11-20-2014 Driver Version 14.501.1003.0 GPU #2 Active false GPU Accelerated Windows 1/1 Direct3D 11 (OMTC) Subsys ID 0b001002 Vendor ID 0x1002 WebGL Renderer Google Inc. -- ANGLE (AMD Radeon HD 5800 Series Direct3D9Ex vs_3_0 ps_3_0) windowLayerManagerRemote true AzureCanvasBackend direct2d AzureContentBackend direct2d AzureFallbackCanvasBackend cairo AzureSkiaAccelerated 0 Important Modified Preferences Name Value browser.cache.disk.capacity 358400 browser.cache.disk.smart_size.first_run false browser.cache.disk.smart_size.use_old_max false browser.cache.frecency_experiment 4 browser.places.smartBookmarksVersion 7 browser.sessionstore.upgradeBackup.latestBuildID 20141126041045 browser.startup.homepage_override.buildID 20141126041045 browser.startup.homepage_override.mstone 34.0.5 dom.mozApps.used true extensions.lastAppVersion 34.0.5 gfx.direct3d.last_used_feature_level_idx 0 media.gmp-gmpopenh264.lastUpdate 1421298605 media.gmp-gmpopenh264.version 1.1 media.gmp-manager.lastCheck 1421298605 network.cookie.prefsMigrated true places.history.expiration.transient_current_max_pages 104858 plugin.disable_full_page_plugin_for_types application/pdf plugin.importedState true privacy.sanitize.migrateFx3Prefs true security.csp.enable false user.js Preferences Your profile folder contains a user.js file, which includes preferences that were not created by Firefox. Important Locked Preferences Name Value JavaScript Incremental GC true Accessibility Activated false Prevent Accessibility 0 Library Versions Expected minimum version Version in use NSPR 4.10.7 4.10.7 NSS 3.17.2 Basic ECC 3.17.2 Basic ECC NSSSMIME 3.17.2 Basic ECC 3.17.2 Basic ECC NSSSSL 3.17.2 Basic ECC 3.17.2 Basic ECC NSSUTIL 3.17.2 3.17.2 Experimental Features Name ID Description Active End Date Homepage

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Try to delete (or rename) the Mozilla folder or the Firefox folder if you have other programs that use the Mozilla folder to store the profile.

  • C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\
  • C:\Users\<user>\AppData\Local\Mozilla\Firefox\Profiles\<profile>\

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

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I want to thank everyone who is trying to help me. I would like to summarize my problem and the steps taken so far to solve it.

FF never saves my setting. I’ll state the more drastic measures I tried since all my other attempts did not help:

  • I uninstalled FF
  • Deleted FF folder under program files (x86) forlder
  • Moved my profile folder to a new location
  • Started FF – a new profile was created with a default profs.js file
  • I changed some setting end exited – the profs.js file was not changed and the setting were not saved.
  • I deleted profs.js file and FF never recreated the file when it was started.
  • I tried changing setting in safe mode and change setting using: about:preferences#advanced. The settings I changed were not saved and profs.js was not changed.

I haven't yet tried the last proposal by cor-el, that is to delete (or rename) the Mozilla folder or the Firefox folder under: C:\Users\<user>\AppData\Local\Mozilla\Firefox\Profiles\<profile>\ (I am not sure I have this folder) Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) as a test.

This is the first time C:\Users\<user>\AppData\Local\Mozilla\Firefox\Profiles\<profile>\ is mentioned. perhaps it holds some answers to this anomaly...

I shall try this in the evening when i get back home. if there are more suggestion i am happy to hear.

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