Are you trying to get into the server management website, the console or the command prompt?
To get to the website, go to
http://youriphere/server-manager and enter admin in the userid field and your admin password in the password field
To get to the console, get an ssh client such as PuTTY, enter your server's ip address in the hostname field, click the radio button for SSH and click the Open button. At the login prompt enter admin for userid and your admin password for password.
To get to the command prompt follow the same directions as for the console but enter root as the userid.
Allan