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Why won't Firefox open

  • 6 replies
  • 2 have this problem
  • 2 views
  • Last reply by cor-el

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Laptop keeps telling me my profile is unavailable or missing. Firefox was installed some time back, and was working. Why does it do this? What is my 'profile'? Why is it missing, suddenly, if it was there before?

Thanks, janet

Laptop keeps telling me my profile is unavailable or missing. Firefox was installed some time back, and was working. Why does it do this? What is my 'profile'? Why is it missing, suddenly, if it was there before? Thanks, janet

All Replies (6)

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Hi there. What kind of computer are you using?

Your profile should be stored in your computer in your user folder. Look for; C:\Users\==<UserName>==\AppData\Roaming\Mozilla\Firefox\Profiles or something like that. What folders are listed?

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What do I do if I can find this user file. At the moment I can't find it. Where do I find it

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Forgot stay, I am using an Optima laptop

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If you can't find the profile folder, let's do this;

Create a new profile. https://support.mozilla.org/en-US/kb/profile-manager-create-and-remove-firefox-profiles

Start Firefox. Is it working now? (Don't worry about the blank profile.)

Look on your desk top. Is there a folder called; Old Firefox?

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Yes, there is a folder called 'old Firefox'. Thank you very much for helping me, by the way.

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See:

This is usually caused by a problem with the profiles.ini file and the profile marked as Default=1 in this file is no longer present on the hard drive.

  • Windows: %AppData%\Mozilla\Firefox\
    C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\
  • Linux: ~/.mozilla/firefox/
  • Mac: ~/Library/Application Support/Firefox/

You can use one of these to make Firefox create/use a new default profile:

  • Delete the profiles.ini file to force Firefox to create a new default profile
  • Use the Profile Manager to create a new profile
  • Use "Choose Folder" when you create a new profile to select the location of a lost profile and recover this profile

It is possible to recover data from the "Old Firefox Data" folder, but be cautious not to copy corrupted files to avoid carrying over problems.