In other words, the system is busy. You will have to wait your turn to access the system. Please try again later. Registration not permitted for this course. The registration period is probably over.
Online registration ends on the first class day of each term.
Students can still drop classes online until the 12th class day. In some cases, you may be able to register through your Academic Advisor even when you get this error message. Student not permitted to register. First check the Holds option on the Student Records menu to see if you have an unpaid fee or the like. If that doesn't clear up the confusion, try using the phone system.