Can I recover history? Assignments and students have disappeared!
Oh no...this doesn't sound good. To be clear, are you saying that the majority of your students are not appearing in your "People" tab of your course any longer? If that is the case, then you will need to reach out to one of the Canvas admins at your school to see if they are able to re-load the students for you. It doesn't sound "normal" that students would be dropped from your course for no reason at all. Assuming that your students need to be re-enrolled, once that has been completed, those submissions *should* reappear in your course.
I hope this helps, Louise!
Louise Emma Whiteley, my recommendation is to check your Canvas test and beta environment to see if any of the information is still there. They are not automatically updated so depending on when students uploaded the assignments you still might be able to access them.
Here are the directions for accessing Beta and Test.
Hope this helps, but if it doesn't then I'd click on the Help link in Canvas and Report a Problem - this is a good way to contact Canvas Support and get higher level assistance.
Thanks for the tip, Kona - that sounds like a good idea. Thankfully though, the students all reappeared in the course this morning, and I've checked that one student who had contacted me about suddenly losing access can now access the course room again. I'll update this thread if my university uncovers the cause of the problem.