I've created a key-pair and have access to a linux instance via FTP and SSH using ec2-user. I have also added the desired user to all groups that ec2-user is in. All of this was tested using the .ppk key, generated my puttygen, which allowed ec2-user to the instance. I even changed the key type from SSH-2 to SSH-1 via puttygen.
I've followed countless guides, but without any luck. Is there anything else I can do?
From what I've read I'll have to create a key-pair (dont know where) for each user, and add one of the keys to a .ssh directory.