Issue
I reinstalled Windows and I'm no longer able to complete the Duo Prompt in Firefox. I receive "500: Internal Server Error" after authenticating with my Directory ID and passphrase at the Central Authentication Service (CAS).
Environment
Resolution
Contact the IT Service Desk for assistance resolving this issue. Alternatively, wait a maximum of 5 days, and the issue will resolve itself. In the meantime, you should be able to authenticate using a different web browser.
Cause
The Duo Prompt is remembering your device from before you reinstalled Windows.