Firefox recover data from old profile

Recover Bookmarks, Password etc in Case of forced new Profile

For Windows 10:

  • Click the menu button, click Help and select More Troubleshooting Information.
  • Under the Application Basics section next to Profile Directory, click Open Directory
  • Your profile folder will open in Explorer
  • Note the first four letters like "3a5b"
  • Note the file size of "places.sqlite" (should be small like 5KB for a fresh profile)
  • Go up one directory level
  • You now see all available profiles.
  • Make a backup copy of the current profile ("3a5b...")
  • Look at the "Date" column and open the directory of an older profile, e.g. from the day before
  • A promising older profile is a few days old and has a file "places.sqlite" which is considerable larger than 5KB
  • Select the following files while holding the [CTRL] key:
    • Copy
    • Go  one folder up
    • Go back to the original profile folder ("3a5b")
    • Paste
    • Start firefox and check if bookmarks, passwords etc are restored.
    • If not try the same with another old profle.