When I open Calendar as an Instructor, I cannot access the attachments and I get a message saying that I am an unauthorized user. Otherwise, it appears that I can access everything else.
Lori, if you are the Instructor looking at calendar entries as an Instructor of that course, then you should be able to access the attachments. My recommendation for something like this is to contact Canvas Support. To do that click on the Help link in Canvas and Report a Problem.
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