6 months ago I purchased a Galaxy Note 5, fingerprint lock/unlock, and a password.

Been using the (thumb) print ever since that time without any problem.

Yesterday I upgraded software. Smooth and easy.

Last night I powered off my phone before going to bed. This morning, powered on, as usual.

Problem: thumbprint not accepted. Need password (which I created 6 months ago, but never had to use).

I should have put password in my computer instead of in my phone. Bad. Cannot remember password!

Anybody have similar experience? Can Samsung Service Center open phone for me?

Too bad that Samsung does not provide warning before installing upgrade.

Appears to be a known problem for the Galaxy S5.....perhaps this will help? Good luck.

"There's a common bug that affects many Samsung Galaxy S5 users, myself included. The software that drives the fingerprint sensor can randomly fail to load, leaving you without one of the most unique features of your beloved smartphone.

When this happens, any attempts to use or configure the scanner result in a message which informs you that the "Fingerprint scanner failed to load. Please reboot and try again." Unfortunately, though, a reboot rarely fixes the issue, so we've got some troubleshooting tips listed below......"

http://gs5.wonderhowto.com/how-to/4-ways-fix-your-galaxy-s5-s-dysfunctional-fingerprint-scanner-0158909/

thanks for the info on Samsung scanner.

I believe my phone is scanning properly, but this new feature requires a password each time I power on "in order to protect my thumbprint":

phone remains locked.