Did your Firefox perform a Refresh? That would have created an Old Firefox Data folder on the desktop with your old profile (settings) folder inside. Do you see anything like that?

If Firefox started performing a Refresh but didn't finish, you may have an additional profile folder on the standard location. To check on that, type or paste the following shortcut into the Windows 7 Start menu search box and press Enter to launch it:

%APPDATA%\Mozilla\Firefox\Profiles

That should expand to the following folder, which is on a hidden path:

C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles

Do you find multiple folders here? If so, do any look recent enough to be the lost settings?

Depending on what you find, we might be able to help you get back to your old settings.

Does the proxy use a secure HTTPS connection or an open HTTP connection?

You may need an older copy of the cert8.db file in case you use a secure connection.

• http://kb.mozillazine.org/Profile_folder_-_Firefox
• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox

Are you still using the same (default) profile or did you possibly switched to a new profile?

Do you have an "Old Firefox Data" folder on the desktop in case you have used the refresh feature?

You can check for multiple profiles via the about:profiles page. You can open "about:" pages via the location/address bar like a web page.

Note that the screenshot didn't attach, so please try again.

See also:

• https://support.mozilla.org/kb/how-run-firefox-when-profile-missing-inaccessible

Yes, I am seeing two folders under the path mentioned by you with the names i17s45x5.default-1385428950802 and 4x5nzlu0.default-1480461168866. Can you please tell me what to do next to restore my old settings.

jscher2000 said

Did your Firefox perform a Refresh? That would have created an Old Firefox Data folder on the desktop with your old profile (settings) folder inside. Do you see anything like that? If Firefox started performing a Refresh but didn't finish, you may have an additional profile folder on the standard location. To check on that, type or paste the following shortcut into the Windows 7 Start menu search box and press Enter to launch it: %APPDATA%\Mozilla\Firefox\Profiles That should expand to the following folder, which is on a hidden path: C:\Users\username\AppData\Roaming\Mozilla\Firefox\Profiles Do you find multiple folders here? If so, do any look recent enough to be the lost settings? Depending on what you find, we might be able to help you get back to your old settings.

Hi jscher2000, Yes, I am seeing two folders under the path mentioned by you with the names i17s45x5.default-1385428950802 and 4x5nzlu0.default-1480461168866. Can you please tell me what to do next to restore my old settings.

It looks that a new profile got created via a refresh: 1480461168866 = November 30

You should have an "Old Firefox Data" folder on the desktop with your previous data. If there are multiple profiles in this folder then check the date stamps to find the most recent profile.

You can use this button to go to the current Firefox profile folder:

• Help -> Troubleshooting Information -> Profile Directory:
  Windows: Show Folder; Linux: Open Directory; Mac: Show in Finder
• http://kb.mozillazine.org/Profile_folder_-_Firefox

You can copy files like these to the current Firefox profile folder to recover specific data.

• bookmarks and history: places.sqlite
• bookmark backups: JSON backups in the bookmarkbackups folder
• SQLite files like cookies.sqlite (cookies) and formhistory.sqlite (saved form data)
• logins.json and key3.db (decryption key) for Passwords saved in the Password Manager
• cert8.db and possibly cert_override.txt for (intermediate) certificates stored in the Certificate Manager
• persdict.dat for words you added to the spelling checker dictionary
• permissions.sqlite for Permissions and possibly content-prefs.sqlite for other Site Preferences
• sessionstore.js for open tabs and pinned tabs and tab groups