Test Pre-requisites The user has private files. The repository File system, Dropbox and Server files are enabled and visible. If using DropBox set the cache limit to 1 Setup Dropbox account Apply for a free/trial account Follow instructions here:  https://docs.moodle.org/27/en/Dropbox_repository Click the "Dropbox Developers" link to go to  https://www.dropbox.com/developers/apps  and sign in. Click on "Create an app" and select "Dropbox API app": Scoped access Full dropbox Make sure your moodle is in https (set the wwwroot to an https protocol and setup the server accordingly, even self signed certificates will work at this stage because the only thing blocking is the actual use of https in the redirect url) Add in the Oauth2 section the redirect url (https://<yoursite>/admin/oauth2callback.php) In permission check: account_info.read (should be checked) files.metadata.read (should be checked) files.content.read sharing.write sharing.read In your Moodle: Add a custom Oauth2 service: (<yoursite>/admin/tool/oauth2/issuers.php) Name it "Dropbox service" Copy the client ID and secret in the related fields Set "Service base URL" to  https://www.dropbox.com/oauth2/authorize Set "This service will be used" as "Internal service only" Then: Go to Site Admin/ Repositories / Manage repositories Enable the Dropbox repository: OAuth2 service to your newly Oauth2 service created (Dropbox service) Cache limit 1 Testing Log in as admin Navigate to your Private Files area. Add a new file, selecting Dropbox as the repository. Select a jpg file and choose the option "Link to the file". Once it is added, VERIFY you will see the arrow icon, indicating it has been linked. Click the "Save changes" button   VERIFY the arrow icon is still there.