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not able to install firefox

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  • Last reply by anupam15

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I have installed firefox but I am unable to open it the system is giving error that failed to read the configuration file contact your system administrator screen shot enclosed for reference

I have installed firefox but I am unable to open it the system is giving error that failed to read the configuration file contact your system administrator screen shot enclosed for reference

Chosen solution

This is caused by some JavaScript file in the "defaults\pref" folder that specifies to process this mozilla.cfg file. This file is likely created by some malware in your case.


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 personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you uninstall and (re)install or update Firefox, 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 create a new profile.


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Seçilmiş Həll

This is caused by some JavaScript file in the "defaults\pref" folder that specifies to process this mozilla.cfg file. This file is likely created by some malware in your case.


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 personal data like bookmarks is stored in the Firefox profile folder, so you won't lose personal data when you uninstall and (re)install or update Firefox, 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 create a new profile.


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Thanks buddy the solution provided by you has worked I am able to use my favourite browser again