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Cannot open Firefox after reinstalling and restarting.

  • 2 replies
  • 1 has this problem
  • 8 views
  • Last reply by cor-el

zaporlaw01
zaporlaw01
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When I try to open Firefox, I get an error message that my profile cannot be loaded. "It may be missing or inaccessible." I deleted and reloaded the program and restarted the computer - twice. nothing. I tried to start the program as an administrator, but that did not work either. It worked until about 10 am yesterday. The other computers in my office can access the program without any problem.

When I try to open Firefox, I get an error message that my profile cannot be loaded. "It may be missing or inaccessible." I deleted and reloaded the program and restarted the computer - twice. nothing. I tried to start the program as an administrator, but that did not work either. It worked until about 10 am yesterday. The other computers in my office can access the program without any problem.

All Replies (2)

Machine Master
Machine Master
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Hey there,

Did you initially download Firefox from an official source?

If yes, you can try resetting Firefox: https://support.mozilla.org/en-US/kb/reset-firefox-to-fix-most-problems?redirectlocale=en-US&utm_expid=65912487-41.djHNRQY0RhaLvvtvcd0BQA.3&utm_referrer=https%3A%2F%2Fsupport.mozilla.org%2Fen-US%2Fquestions%2F965458&redirectslug=reset-firefox-fix-most-problems

Hope this helps :)

cor-el
cor-el
  • Moderator
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A possible/likely cause is 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