Try this: https://support.mozilla.org/en-US/kb/restore-bookmarks-from-backup-or-move-them

You would only get the import wizard if there is no profiles.ini present that registers all profile folders.

It is possible that there has been a problem with the profiles.ini file that registers profiles and that a new default profile got created.

You can check if you have orphaned profiles that aren't registered in profiles.ini and that do not show in the Firefox Profile Manager. You can check that by opening the current profile folder and go up one level.

• http://kb.mozillazine.org/profiles.ini_file

You can use the button on the "Help -> Troubleshooting Information" (about:support) page to go to the current Firefox profile folder.

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

See also:

• https://support.mozilla.org/en-US/kb/how-run-firefox-when-profile-missing-inaccessible

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

https://addons.mozilla.org/en-US/firefox/addon/febe/ FEBE (Firefox Environment Backup Extension)

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 backups of files that you choose.

https://addons.mozilla.org/en-US/firefox/addon/opie/ OPIE

Import/Export extension preferences

Another post about finding old profile files when Firefox has lost track of them: https://support.mozilla.org/questions/1160506#answer-969338