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The student files will be downloaded as a .zip file. Unzip the file to see a folder containing the student submissions.
If using the Safari browser, you may need to edit settings and uncheck “Open ‘safe’ files after downloading” in order to download all files. If this setting is checked, only one student submissions may show up.
Additional Notes
By default, Moodle will create a folder for each student and put their file(s) inside the folder. If students are only submitting a single file, the additional folders can be cumbersome. Most instructors will want to uncheck Download submissions in folders at the very bottom of the "View all Submissions" page:
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