Hi Tim, try to start Firefox into profile manager (in Windows press the Win+R buttons and enter firefox -p). Hopefully it shows your old profile as an option.

Otherwise, this article should provide information to find and restore an old profile: https://support.mozilla.org/en-US/kb/back-and-restore-information-firefox-profiles

Good luck!

Thank you very much for your answer. The profiles were deleted, and my PC can't find the path to profile files. Is there any hope?

Hello,

It seems Firefox has reset itself, which is strange. Do an Virusscan/adware of your Pc, also delete pls the old firefox data from your harddrive, revo uninstaller can help with that, if you dont know how to do it manual, it is a small little tool, no background proz etc,free.Browser cleaner tab. Do you have many add-ons? It sounds like the extensions are interfering with each other. I would only use an ad blocker. Everything else just clutters things up. If I were you, I would remove all add-ons and only download the essentials again. I would also delete all old Firefox data that's still on your PC. Ghostery/uBlock and a translation tool—many apps install junk along with other programs; these could have caused the crash and hard reset. That would be my first guess. Maybe its all back after the profil login, i dont know ;)

Bla bla : i guess this is enough info . All Above is opt.

About your profile:

In the top right corner, you'll find the menu by the three horizontal lines. At the very top, click "Log in." Now you can log in again with the email address associated with your profile. If you've forgotten your password, you'll find recovery options at the bottom. After logging in again, click in the top right corner and then "Sync." It should then retrieve your bookmarks from the cloud, and everything should look like it did before.

Best regards, Miss Take,

sry englisch is hard ;) good day

See also:

• https://support.mozilla.org/en-US/kb/recover-user-data-missing-after-firefox-update