php-login-script: Warning: Undefined array key "thumbprint" user.php on line 284

Hi, I download and install the php-login-script zip file in www folder of Wamp Uniserver. I followed the instruction to create user.db but when i run index.php, i get this message on 2 lines: "Warning: Undefined array key "thumbprint" in W:\UniServerZ\www\SQLite-PHP\user.php on line 284 You are not logged in. Log in now or Sign up" I tried to "Log in" or "Sign up" and i get the message login not found and signup not found but the 2 php files are in the localhost root directory !!! Thank you for your help. Regards Maurice at [email protected]