Module completions are based on whatever state a module was in when a user completes it. For example, let's look at the following scenario:
- You create a (manually-completed) module with a single test and nothing else.
- An end user opens that module, passes the test, and clicks Mark Done.
- That module will be marked completed for that user forever.
- Even if you later add other required components to the module, that user will still show up in all reporting as though they have completed the module, even though they have not completed the current content within the module.
There is no way to update a piece of media or eLearning Content within a module. The only option is to remove the media, and replace it with a new version. Note that although users who have previously completed the module (see above) will still show the module as complete, the new components will be marked as incomplete.
An interesting behavior to note here is that if you have a Gate in your module, and then add/replace some content before the Gate (which the Gate requires), even users who have previously completed the module will be unable to access the content below the Gate until the complete the new content.
If a standard module is created with auto-complete enabled but there are no required items in the module, auto-complete will not be able to complete the module but will instead display the Mark Done button for the user to complete the module when they are done.
Note: You should never delete a piece of media that has been used in a module as the completions for that piece of media are stored separately from the module itself. Deleting the media will destroy all records of users' interactions with that media.