All UK2 customers have a username, but it was previously called an account name, and it was automatically generated based on your email address, for example: email@example.com/1.
For a limited time you can still log in as you used to with your domain name, server number or @uk2.net email address and the associated password. In the top right-hand side of the page you will see your username displayed once you've been successful (you are logged in as 'your username').
If this is the first time you've logged in you will be prompted to choose a new, more memorable username, and to confirm the contact details that we have for you.
Don't forget you can also get into your account via the old control panel for now.