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My firefox lost all data of my settings and reinstalled itself

  • 2 replies
  • 1 has this problem
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  • Last reply by FredMcD

It started after the power went out I went to open Firefox and it acted like it was installing for the first time and it lost ALL of my settings. These settings were really important and I need them back. I had Firefox sync setup for this very reason but I could not figure out how to sync the browser with the settings that were synced with my account.

It started after the power went out I went to open Firefox and it acted like it was installing for the first time and it lost ALL of my settings. These settings were really important and I need them back. I had Firefox sync setup for this very reason but I could not figure out how to sync the browser with the settings that were synced with my account.

All Replies (2)

Hi, first look on your Desktop for a folder named Old Firefox Data (see Refresh Firefox - reset add-ons and settings). If it isn't there, for bookmarks only, you can try this: Open bookmarks > Show All Bookmarks > Import and Backup > Restore, and see if you have a backup there.

If not, and for other settings please see -


Incidentally, you have more than one version of Shockwave Flash - which can cause problems, so all but the latest should be removed from your machine -

If your question is resolved by this or another answer, please take a minute to let us know. Thank you!

These can't get your data back, but will help in the future.

These add-ons can be a great help by backing up and restoring Firefox

FEBE (Firefox Environment Backup Extension) {web link} FEBE allows you to quickly and easily backup your Firefox extensions, history, passwords, and more. In fact, it goes beyond just backing up -- It will actually rebuild your saved files individually into installable .xpi files. It will also make backups of files that you choose.

OPIE {web link} Import/Export extension preferences