Where does Android store fingerprint data? I am looking for the files that correspond to the recorded fingerprints on my Nexus 6P and a way to "reset" the fingerprint system. Something similar to how Android stores lock screen settings (pattern etc.) under /data/system/locksettings.db*, and you can remove the lock screen by deleting these files (if you have root access).

The reason I am asking is because after a TWRP restore on a new Nexus 6P, my fingerprint hardware is not working anymore. The error message is Fingerprint hardware not available. Also see this question: &quot;Fingerprint hardware not available&quot; after TWRP restore

All five previously recorded fingerprints show up on the settings UI, but I am not able to delete them by clicking "Delete".
try removing these files also

/data/system/users/0/fpdata/user.db
/data/system/users/0/settings_fingerprint.xml


Instead of removing files, appending the filenames with some random extension would be better. So, if anything goes wrong we can revert the changes. 
eg: user.db -> user.db.xyz or xyx_user.db

I faced the same error too and this worked for me.