When Moodle loses access to a personal OneDrive, either because your token has expired or you’ve manually removed access from your Microsoft Account Settings, you can still browse files and add them as an assignment submission. From the user’s POV, this appears to work, but Moodle actually attaches a file (with the same name and format as the one you tried to submit) to the assignment, but which contains an authentication error message, and not the content of the expected file. 

This also probably affects the Google Drive and Dropbox repositories but have not tested with these.

• Ensure you have a personal OneDrive account with a PDF file containing some text uploaded to it. 
• Ensure you’re logged out of the OneDrive Moodle repository.
• Ensure you have access to a Moodle course and are enrolled with a student role.
• Ensure the Moodle course has two assignments, both with the default settings.
• Enable and configure the OneDrive repository in Moodle.

Submit to assignment 1 

1. Switch to the student role. 
2. Add a submission to the first assignment. 
3. Select the OneDrive repository. 
4. Login and authorise Moodle to access your personal OneDrive account 
5. Select your PDF file from OneDrive. 
6. Save your submission. 
7. Download the PDF and observe that the file is the same one you uploaded. 

 Remove OneDrive permissions 

1. Access the [App Access page in your Microsoft Account (still using your personal OneDrive) 
2. Locate your Moodle connection
3. Click the Details link and then Stop Sharing 

Submit to assignment 2 

1. Add a submission to the second assignment. 
2. Select the OneDrive repository. 
3. Observe that you can still browse and select files. 
4. Select the same PDF file from OneDrive. 
5. Save your submission. 
6. Download the PDF and observe that it will no longer open without an error message. 
7. Open the downloaded PDF file in a text editor and observe the authentication error has been placed in the document and that the document you submitted is not actually submitted to the assignment.