When I sign in, I am prompted to obtain a secure access code. What do I do and how is it used?

In order to confirm your identity and register your computer we need to send you a secure access code. You can choose a phone number to receive the code by voice or text. After entering the secure access code, you can activate your computer for later use or only allow one-time access if you are using a public computer. If you elect to activate your computer for later use, in the future you will login by entering your login ID and password.