Hi, first try restarting Firefox - 3-bar menu > Exit Firefox in bottom right corner.

If that doesn't help, and in case a Refresh has occurred, please look on your Desktop for a file named Old Firefox Data - Refresh Firefox - reset add-ons and settings.

If the file isn't there, you can try this: Open bookmarks > Show All Bookmarks > Import and Backup > Restore, and see if you have a backup there.

If not, please see -

• Profiles - Where Firefox stores your bookmarks, passwords and other user data.

• Recovering important data from an old profile.

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

went to profiles- nothing there from before the date I lost bookmarks. Am in process of putting everything back manually.

Do you have an "Old Firefox Data" folder on the desktop in case the Refresh feature in Firefox has been used and a new profile has been created?

• https://support.mozilla.org/en-US/kb/reset-firefox-easily-fix-most-problems

It is possible that there has been a problem with the profiles.ini file that registers profiles and that a new default profile got created.

You can check if you have an orphaned profile that isn't registered in profiles.ini and that does not show in the Firefox Profile Manager. You can check that by opening the current profile folder and go up one level.

• http://kb.mozillazine.org/profiles.ini_file

If you have found an orphaned profile then you may want to recover some personal data.

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder or use the about:profiles page.

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox
• C:\Users\<user>\AppData\Roaming\Mozilla\Firefox\Profiles\<profile>\