Overview
Students click on a link from the Canvas To Do list or from inside a module and get a pop up error message within the Canvas course that states "access denied"
Explanation
"Access denied" messages from within Canvas are related to content that the instructor has locked. An instructor may lock Canvas content by date (not available until...) or by setting pre-requisite requirements that must be completed first before the content can be accessed.
For example, instructors may design their course so that students have to progress through activities in a specific order. Students in such a course may receive an "access denied" alert when they try to enter a new assignment before they've completed the assignment that came before it in the course.
Access details, including specific dates or prerequisite requirements can be viewed in the Canvas Modules view. For more information, check out the detailed description about viewing locked content details in the Canvas Guides.
Note: The eLearning Helpdesk will not unlock Canvas course content. Instructors control access to their course content, so only the course's instructor can unlock Canvas course content.
Solution
If students need access to course content that is locked, they should contact their instructor via Canvas Inbox.