If there is no network connection for your mobile device (e.g. the wireless network is down or out of range), or you are out of the country, you still authenticate at a multi-factor authentication (MFA) prompt by using a passcode.
- Open the Duo Mobile app on your mobile device.
- Tap the key icon to generate a six-digit passcode.
- Return to Choose an authentication method window on your computer or device. Click Enter a Passcode.
- Enter the passcode generated by the Duo Mobile app in the Passcode field.
- Click Login.