I'm still having this problem. Somewhere between uninstalling Norton 360 and installing Bitdefender Total Security 2014 it happened. I've tried the method mentioned in this thread, reinstalling the Validity Sensor driver, and reinstalling Simplepass 6.0.100.272 but it still fails. I keep getting the error message that the fingerprint match was not found in the db. I've tried multiple fingers and have re-enrolled them a few times.
What should I do?
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EDIT: Solution was to delete all of my fingerprints and start over. I think reinstalling Simplepass would have worked too if I had chosen to delete all user data.