I'm fairly new to AWS and I'm trying to create an Amazon Linux server to run PHP code. I'm following the [tutorial](http://docs.aws.amazon.com/AWSEC2/latest/UserGuide/install-LAMP.html) on AWS, but I can't connect to my server using either the public DNS or IP address. The error I'm getting is "This site can't be reached. *Public DNS* refused to connect". The instance is currently running, and I've successfully connected to it using puTTy and WinSCP. I double-checked the security group for my server, and I have port 80 open to all IP addresses.