Unable to create new account in Grafana

I installed Grafana4.4.3 on CentOS. I change the IP address and Port in grafana.ini file. When I open it in browser, it takes me to Log in page. When I enter the credentials, it says “Unauthorized”. Also, I cannot find the option for Sign Up. How should I create a new account in Grafana?

the default admin user is username: admin , password: admin

I installed an older version and now its working for me.