Problem

If a student gets this message, then the class invitation link that students use to create their accounts and enrolled in their class and activated has expired or been deleted.

Solution:

Usually, to solve this problem, the instructor should log into their account, click the three stacked dots to the right of their class, and choose either the Invite students: View/Edit Class link option. Then they should click to edit the reservation, choose how many more licenses need reserved for the class, and edit the expiration date to be in the future (usually by a couple weeks), then Save. After they have done this, the student can try their link again.

See full guide to editing a class invitation link here, if additional guidance is needed: https://support.testout.com/hc/en-us/articles/4423172994715