I don't think there is any secret backup for deleted passwords.

Saved passwords actually are stored in a file named logins.json and the key used to decrypt them is stored in key3.db. So assuming that logins.json was cleared, you would need to find an earlier version.

If you do not make regular backups, one possible source of an earlier version is a Windows restore point. In Windows 7, you can check for such an earlier version as follows:

Open your current Firefox settings (AKA Firefox profile) folder using either

• "3-bar" menu button > "?" button > 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 "Show Folder" button. This should launch a new window listing various files and folders in Windows Explorer.

Find logins.json, right-click it, and choose Properties. Then click the Previous Versions tab. Windows should search its restore points and list what is available. IF YOU DECIDE TO TRY RESTORING SOMETHING, PLEASE EXIT OUT OF FIREFOX FIRST. Otherwise, you might lose the backup.

Note: Windows hides some file extensions, so if you do not see logins but not logins.json, I suggest turning off this annoying feature. See: http://windows.microsoft.com/en-us/windows/show-hide-file-name-extensions

Note #2: I suppose it's possible that instead of emptying logins.json Firefox might have deleted the file. In that case, try saving a new password so there is a file there so you can use the Previous Versions feature.

Any luck?

To get back erased logins you would need a backup copy of the logins.json file.

You can check if there is a previous version of the logins.json file available.

• Right-click: Properties > Previous Versions
• http://windows.microsoft.com/en-US/windows7/Previous-versions-of-files-frequently-asked-questions

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

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

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 backup of files that you choose.

OPIE {web link} Import/Export extension preferences