If the Duo mobile application is deleted from a mobile device that needs to be setup again, the device will need to be reactivated in the MFA Portal. 

Use the following steps to reactivate the Duo account. 

1. Visit duo.okstate.edu 
2. Authenticate using your O-Key credentials.
3. Authorize your login to MFA using another method setup besides Mobile.
4. After you have authenticated successfully, click the Add Devices link in the Setup section of the MFA Portal page.
5. Authorize your login again with MFA using another method setup besides Mobile.
6. After you have authorized your login, click the Device Options button next to the mobile device that the Duo app was reinstalled on. 
   • • To reactivate a previously used device, select "I have a new phone."
7. Select the Reactivate Duo Mobile button.
8. Choose the type of device (iPhone, Android, Windows Phone, Other) from the list of options and then click Continue.
9. Select the I have Duo Mobile installed button.
10. The QR code should then appear to scan with the mobile device’s camera.
11. Complete setup on the mobile device and web browser.