see this answer:

• https://support.mozilla.org/en-US/questions/1134239#answer-905210

Please update to Firefox 62, 50 is no longer supported or safe to use.

You should also update to at least windows 8.1, or 10 if you can

FFus3r said

see this answer:

• https://support.mozilla.org/en-US/questions/1134239#answer-905210

restore the key4.db file

Hi fredfran, Firefox does not have an "undo" feature for saved logins you delete or edit. That would be nice! Maybe a third party product dedicated to passwords (e.g., a cloud-based product) can remember more logins.

Windows Vista and newer have a limited kind of backup, a "shadow copy" created when you install Windows updates, and sometimes when you install other software. DO NOT USE SYSTEM RESTORE! That could cause much more data loss. You can instead use a third party tool to look inside your recent restore points, if any, for files you want to export out. Here are the steps:

(1) Set Windows to show hidden files and folders:

https://support.microsoft.com/en-us/help/14201/windows-show-hidden-files

(2) Download and run one of these programs:

• ShadowExplorer: http://www.shadowexplorer.com/
• System Restore Explorer: http://nicbedford.co.uk/software/systemrestoreexplorer/

Within the most recent restore point shown in the program, you can explore along this path to see whether you can find a recent shadow copy of your profile:

\Users\your-user-name\AppData\Roaming\Mozilla\Firefox\Profiles\

(3) Export a recent copy of the following files to a convenient location such as your currently live desktop. Then you can try to swap them into your currently active profile in place of what's there to see whether that brings back your passwords.

• logins.json
• key4.db *
• key3.db *

* Firefox switched to key4.db at some point, so if it's missing for an old version, or if key3.db is not present with a newer version, don't worry about it.

If you found some candidate files to try...

(1) From inside Firefox, open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" Help > Troubleshooting Information
• (menu bar) Help > Troubleshooting Information
• type or paste about:support in the address bar and press Enter

In the first table on the page, click the "Open Folder" button. This should launch a Windows Explorer window listing the various files and folders in your profile.

(2) Leaving that window open, switch back to Firefox and Exit, either:

• "3-bar" menu button > "power" button Exit
• (menu bar) File > Exit

Pause while Firefox finishes its cleanup, then:

• right-click > Rename logins.json to loginsOLD.json
• right-click > Rename key4.db to key4OLD.db
• right-click > Rename key3.db to key3OLD.db

(3) Then copy/paste into the folder the files you extracted from the restore point.

When you start Firefox, it should use those older files. Success?

hey tyler, your "advice" has less value than spam...

jscher2000 YOU ARE AWESOME!!!

youre a genius, your level of knowledge is amazing, I would give you a big hug and a hi five if I could.

It worked, I did exactly like you said. I downloaded shadow explorer.

I had just done a restore operation and I thought oh no it wont work.

But I was able to find very easily, a logins.json file from 8/25 (restore point was 9/2) and I put it in the mozilla profiles folder in place of the logins.json file that was missing my passwords and logins.

and voila! got em back!

LOVE YOUUUUU!!!!! BIG THANK YOU jscher2000 :)

fredfran said

hey tyler, your "advice" has less value than spam...

Tyler Downer gave you excellent advice, with only your best interest at heart.

So much for appreciation .....

Hi fredfran, now that you have your data back, it is time to discover why you still run Firefox 50 and not a later version. Mozilla discloses security issues that are fixed in each release, so unfortunately, the issues in older versions of Firefox are out there in the hackers' playbook and it could be just a matter of time...

Note that in Windows 8 you can also check in Windows Explorer via the right-click context menu in the properties if there is a previous version of a file (logins.json, key3.db/key4.db) is available.

• right-click: Properties -> Previous Versions
• https://support.microsoft.com/en-us/help/17128/windows-8-file-history