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I changed my Firefox Preferences and now Firefox will not open.

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

beckyacuna
beckyacuna
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I changed my Security and Privacy settings and deleted my cookies. When I tried to open Firefox, it would not open. I deleted Firefox from my Mac Applications, used Safari to download Firefox 42.0, and Firefox will still not open. How can I fix this? (I ALWAYS use Firefox rather than Safari.)

I changed my Security and Privacy settings and deleted my cookies. When I tried to open Firefox, it would not open. I deleted Firefox from my Mac Applications, used Safari to download Firefox 42.0, and Firefox will still not open. How can I fix this? (I ALWAYS use Firefox rather than Safari.)

Chosen solution

Thank you. I'm good now. I appreciate your help.

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All Replies (3)

cor-el
cor-el
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  • Top 10 Contributor
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Try to start Firefox in Safe Mode by holding down the Shift (Mac: Options) key to see if that works.

Try to delete possible user.js and numbered prefs-##.js files and rename (or delete) the prefs.js file to reset all prefs to the default value including prefs set via user.js and prefs that are no longer supported in current Firefox releases.

You can find the Firefox profile folder in this location:

  • ~/Library/Application Support/Firefox/Profiles/<profile>/

In Mac OS X v10.7 and later, the "~/Library" folder is a hidden folder.

beckyacuna
beckyacuna Question owner
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Chosen Solution

Thank you. I'm good now. I appreciate your help.

cor-el
cor-el
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  • Top 10 Contributor
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You're welcome.