Duo user log in error: Access Denied

Where an organisation uses Duo to enforce device health or device trust requirements, some users may see an Access Denied message during sign-in, advising that their organisation has blocked the device from accessing the application.

This is typically caused by the Duo device health application installed on the computer - listed as Duo Desktop, or Duo Device Health Application on older versions - being in a corrupted, stalled or out-of-date state. When this happens, the application cannot correctly report the device's health back to Duo, and Duo blocks the sign-in as a precaution.

In most cases the issue is resolved by removing the existing application and installing a fresh copy when prompted at the next sign-in. Follow the steps below to correct the issue.

Uninstall the Duo device health application

Note: Removing this application usually requires local administrator rights.
If you do not have administrator access to your computer, contact the Real 
World Technology Solutions support team for assistance.

1. Close the browser window or tab displaying the Access Denied message.
2. Click the Start menu, then open Settings.
3. Go to Apps, then Installed apps (on some versions of Windows this is Apps & features).
4. In the search box, type Duo to locate the installed application. Depending on the version installed, this will appear as Duo Desktop or Duo Device Health Application. If both are listed, remove both.
5. Click the ⋯ (three dots) next to the application, then click Uninstall. Confirm Uninstall when prompted, and complete the removal wizard.
6. Once removed, restart the computer to clear any remaining application processes.

Reinstall the application and sign in

1. Attempt to sign in again to the service that previously displayed the Access Denied error.
2. After a short pause, the Duo prompt in your browser will load a download prompt for Duo Desktop. Follow the on-screen instructions to download and run the installer.
3. Complete the installation, then continue with the sign-in.

Duo Desktop runs in the standard user context and performs its health check automatically during authentication, so no further action is required. If the Access Denied error persists after reinstalling, please log a request with the Real World Technology Solutions support team.