Add User to Past Courses
USF Institutional Canvas courses, that is, courses that are created directly from Banner, are automatically concluded 6 weeks after the official term end date as specified in Banner. In this state, the course becomes “read-only” for students and new people cannot be added- the + People link becomes greyed out.
What you can do to as workaround is to temporarily “activate” the course again by overriding the currently specified Term availability dates for the course.
- Go to your Canvas Course and select Settings from the Left Navigation Menu in Canvas 
- Make sure to Click on the Course Details Tab 
- Toggle the Participation dropdown box from Term to Course 
- In the End field, click on the Calendar icon and enter a date sometime in the future  (usually the next day is fine). Note: You cannot leave this field blank.
- Save your changes by selecting the Update Course Details  button at the bottom of the screen. Now, the +People link will be active and you can add users again.
- If you are adding a fellow instructor to the course, please choose the "copy" role from the list of available roles in the +People box. This will provide this person the ability to see all content, copy it into their own course, but not make any changes or deletions to your original course.