hello, To restore this data:

On the desktop you should see a folder called 'Old Firefox Data' open it and copy all the data by highlighting and selecting everything in that folder, then right click and select copy. Now open FIrefox. Head on over to about:profiles by typing it in your URL bar. Click on the Open Folder button under the Local Directory, not root. Then right click when inside the new profile folder and select paste. Then restart Firefox. You should now have all your previous passwords, and data back.

If this solved your problem, mark as solution.

logins.json and key3.db [v58+]key4.db : These are the password files. Copy Both !

Hi there, Anamika that was a thorough step by step. Thank you but it did not work. I did exactly what you suggested no data has transferred

Did you shut Firefox down before doing the copy? Any error messages?

You need matching logins.json and key4.db files to transfer the passwords.
d you check i a text editor or in Firefox (open file) that logins.json does contain login data ?

You can copy specific files with Firefox closed to the current profile folder to recover personal data.

• https://support.mozilla.org/en-US/kb/recovering-important-data-from-an-old-profile

• bookmarks and history: places.sqlite
• favicons: favicons.sqlite
• bookmark backups: compressed .jsonlz4 JSON backups in the bookmarkbackups folder
• cookies.sqlite for the Cookies
• formhistory.sqlite for saved autocomplete Form Data
• logins.json (passwords) and key4.db (58+) or key3.db (57 and older) (decryption key) for Passwords saved in the Password Manager
  if you only have key3.db then make sure to remove an existing key4.db
• cert9.db (58+) or cert8.db (57 and older) for (intermediate) certificates stored in the Certificate Manager
  if you only have cert8.db then make sure to remove an existing cert9.db
• persdict.dat for words you added to the spelling checker dictionary
• permissions.sqlite for Permissions and possibly content-prefs.sqlite for other website specific data (Site Preferences)
• sessionstore.jsonlz4 for open tabs and pinned tabs (see also the sessionstore-backups folder)