key3.db [v58+] key4.db and logins.json These are the Password files

Both must have the same time/date stamp. Did you overwrite the current files when you copied these? Did you remove the key4 file?

All of the info I found online said just two files needed to be copied over. The Key3 and the logins. I did nothing with the Key4. Yes, I overwrote the current files when copied.

If the old profile had a key4.db file then you need to copy that key4.db file and logins.json. If you only have logins.json and key3.db then you need to remove an existing key4.db file. If you do not have access to the old device and can't remember if it had a key4.db file then you might be out-of-luck if the key3.db file isn't working.

Wow, removing the Key4 from current profile did the trick. Thank you so much. All my saved logins have been restored.

I am glad to hear that your problem has been resolved. If you haven't already, please select the answer that solves the problem. This will help other users with similar problems find the solution more easily.

Thank you for contacting Mozilla Support.

In the event that the passwords information is lost, you should record all information in a separate text file somewhere else on your hard drive, or written down. You can easily copy and paste if you need to do so. If you are concerned about someone else looking at that file, you can compress it using a password.

http://www.nirsoft.net/utils/passwordfox.html PasswordFox v1.58 - Extract the usernames/passwords stored in Firefox Copyright (c) 2008 - 2017 Nir Sofer

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