ADD users in AWS - group add issue

http://www.edukatr.com/how-to-start-an-ec2-ubuntu-server-for-your-developer-in-6-minutes/

http://codingthis.com/platforms/creating-new-linux-users-and-login-keys-on-amazon-ec2/


ps:-
group add issues
http://www.linuxforums.org/forum/newbie/181819-chown-invalid-user-problem.html