When I try to get updates I see an Authentication required dialog box. I tried the password I set-up during installation but is fails. What is the authentication?
If you are sure you've forgotten your password (check caps lock, typos etc) you can try and reset it using recovery mode as per https://askubuntu.com/questions/24006/how-do-i-reset-a-lost-administrative-password. Should be similar for elementary OS.