i followed all your steps to login to my amazon ec2 cloud server, when i start putty and start my ssh session i am able to get to the login prompt but when i enter the root user putty stops working and gives me this error message:

Server refused our key

what does it mean?

well, im gonna give you the answer. i spent some time trying to figure this out, so what you need to do is login as ec2-user

after you enter ec2-user as the user, use the password for your ec2 panel. it uses the same password

after that a welcome message that looks like this:
Authenticating with public key "imported-openssh-key"
Last login: Fri Dec 23 00:20:13 2011 from localhost

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