File not found
The URL of the original file is not valid or the document is not publicly accessible.
Verify the URL is correct, then contact the document owner.
Kevin, this is a strange error message. I've been using Canvas since 2012 and haven't seen this one before. Have you tried having students resubmit their documents? I'd try having them resubmit and if that doesn't work, then I'd contact Canvas Support (Help link --> Report a Problem).
Kevin, I agree with Kona Jones that support is in the best position to investigate this for you. The only time I can recall seeing a message anything like this is when a student submitted a desktop shortcut to a file rather than browsing for and uploading the actual file. It's odd that it's happened more than once, though.
Were you able to find an answer to your question? I am going to go ahead and mark this question as answered because there hasn't been any more activity in a while so I assume that you have the information that you need. If you still have a question about this or if you have information that you would like to share with the community, by all means, please do come back and leave a comment.
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