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Firefox does not open, but instead gives the error message, "Failed to read the configuration file." It has worked in the past, but not now.

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  • Last reply by John99

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Firefox does not open, but instead gives the error message, "Failed to read the configuration file." It has worked in the past, but not now.


I REINSTALL 10 TIMES SO DON'T TELL ME THAT!!! I'm piss because i need firefox working again so i can finish reseaching my speech in 5 days.

Chosen solution

Yes, deleting Firefox program file.


Comment from moderator. Please see other posTs in this thread such as https://support.mozilla.org/en-US/que.../964939?page=3#answer-456928

Read this answer in context 👍 0

All Replies (16)

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Both, first uninstall Firefox and then delete the Firefox program folder if it is still there.

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Can't deleted Firefox folder writed- proteced

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Do you mean a password is required to remove it? Your hard drive cant be write protected.

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firefox is protected

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Maybe we are at last getting somewhere.
We seem to have established you have so far been unable to successfully complete the instructed clean reinstalls.

I do not have time to engage in long answers today, but I am sure others will have, however

  • please try to give longer answers yourself
  • and please explain any problems you have trying to follow our detailed instructions.

We have no way of knowing what you are doing, or what problems you encounter, other than from what you say to us. if you miss out an important step in an instruction that whole process will probably not work as intended; even if you repeat it 10 times

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renamed / deleted is local-settings.js file, if present in the \defaults\pref folder which points to mozilla.cfg

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where can can i found this folder at? renamed / deleted is local-settings.js file, if present in the \defaults\pref folder which points to mozilla.cfg

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Hi again, I am hopping with most of the information in one place it should make this easier to follow, because I know these instructions are not straight forward. You may wish to copy or print this information before you begin.

I will try to explain again what you need to do by combining the information from three of my earlier posts 1, 2, 3 .

Is there any possibility

  • You are failing to delete the correct folder when doing a clean install
  • You have security software that prevents deletion of certain Files, or is recreating them.

Suggestion next time you try a clean reinstall,

  1. Delete the Firefox program files (* see under)
  2. Check that the files have been deleted
  3. Shut-down then reboot the computer (but do NOT re-install Firefox)
  4. Double check to ensure files are gone on restart.
  5. Only if the Files are not there re-install Firefox
*The instruction

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\"
  It is important to delete the Firefox program folder to remove all the files and make sure that there are no problems with files that were leftover after uninstalling.
  http://kb.mozillazine.org/Uninstalling_Firefox

Please say

  • What; if anything; was not explained well enough for you to understand it.
  • What you did actually do,
    • Which suggestions have you managed to follow ?
    • Did you have problems or error messages ?
    • Did the instruction appear to go as expected ?
      (still not working lets us know you still have the problem, but is not very informative as to whether the proposal was actually tried and whether it appeared to succeed in for instance a clean install)

You may be trying to follow this from emails, if so it may be easier if you look at the forum thread as well and scroll through it.

   Your Thread https://support.mozilla.org/en-US/questions/964939 

N.B.

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where Firefox program locate under control panel?

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Boot the computer in Windows Safe mode with network support (press F8 on the boot screen) as a test to see if that helps to remove the Firefox program folder.

Try this program:
UNLOCKER 1.9.2 BY CEDRICK 'NITCH' COLLOMB: http://www.emptyloop.com/unlocker/

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Some additional notes that may assist you

  1. The intentions to delete the folder by for instance right clicking it and taking the delete option. This does not involve using the Control Panel.
  2. A pdf format guide that may help if you are new to Windows XP, in particular pages12-17 deal with Windows Explorer including navigating & deleting folders
    https://vula.uct.ac.za/web/learnonline/manuals/CET%20Windows%20XP%20Training%20Manual%20v1.1.pdf
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I'm the administrator

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First I'm sorry if I was rude. Second I got my firefox to right again.Third I want to say thanks to everybody for helping me.

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Glad you fixed it then.

Was it deleting the Firefox program folder that solved the problem, or did you find someone to fix it for you. Teenage relatives are often Wizards with computers.

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Chosen Solution

Yes, deleting Firefox program file.


Comment from moderator. Please see other posTs in this thread such as https://support.mozilla.org/en-US/que.../964939?page=3#answer-456928

Modified by John99

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Ok thanks for the reply . In case anyone else needs a solution I have marked your own reply as a solution but will also link that to other answers.

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