An Authorization Code is a 8 to 32 character code assigned by the provider or host of your domain (Registrar) at the time a domain name is created or after it is transferred. The authorization code is basically a password for transfer of the domain. Authorization codes are an extra security measure, ensuring that only the owner of the domain can make transfers.
All .com, .net, .org, .info, .biz, .name and .us domains require an authorization code. If you do not know your authorization code or are getting a Authorization Code Rejected notice, please contact your Registrar for the correct information. Once you have it, you can update the authorization code of your domain through the Hosting Control Panel. Please have it ready before you initiate a domain transfer.