Linked files in instructions

I hyper-linked a word in the instructions of an assignment to a PDF file.  When the students clicked on the link they get a blank screen with the word "unauthorized" in the upper left corner.&nb...

How can I tell if a student has viewed an assigned video?

I have assigned a point value to videos I have assigned the students to view.  How can I tell if they have viewed the video?  Will it automatically appear?  Do I have to check the anal...