Course Search & Enroll - "You do not have a valid appointment" Error
This document explains the meaning of the "You do not have a valid appointment" error message and how to resolve it.
What it means:
To enroll in classes, you are assigned a specific enrollment appointment time, which is the earliest that you can begin enrolling in classes for a term.
This message usually means you're trying to enroll in classes too early, either before the appointments have been assigned, or before your personal appointment time has arrived.
cancel Enrollment failed:
You cannot enroll at this time. Your enrollment appointment is in the future or open enrollment has not yet begun. Check Student Center in MyUW for your enrollment appointment or contact us for assistance.
Find your own enrollment appointment time, when and how these are assigned to students.
After appointments are assigned, you can find yours on the "Course Search & Enroll" tile in MyUW: 
The assigned appointment time will also appear in your Course Search & Enroll cart: 
Your enrollment time has arrived but you're still seeing an error message?
You might still be seeing an error message from the last time you attempted to add the course to your cart or enroll. The message does not refresh/revalidate and will stay on the page until the next time you try to enroll.
This means that if, according to your enrollment appointment, you should now be able to enroll, you can select the checkbox next to the course and click the "Revalidate button", or simply disregard the error message, select the checkbox next to the course and then and click the "Enroll" button. 
Please contact the Office of the Registrar if you believe enrollment appointment times have been assigned to students and you do not have one.