Make sure that you are using the correct username and password:

Your username is the same as the username you use to log into your computer. ex. astudent28 (make sure you don't include your full email address.) The password is the same as your laptop password. 

example:

Username: astudent28

Password: 123456@ccsd

If campus asks you for an email address put your full CCSD email address. 

Example: astudent28@clarke.k12.ga.us