So I just launched my ec2 instance : t2.micro with Ubuntu 14.04 OS. The security group has settings enabled for letting in inbound traffic from SSH ( port 22 ) and HTTP ( port 80 ). But when I try to reach the server from the browser via its public dns : ec2-52-74-136-74.ap-southeast-1.compute.amazonaws.com it says connection refused. And if I try to ssh it says : Permission denied (publickey). Any ideas?