Duo RDP not prompting when signing into Windows via Network Sign-In

[bblair]

We currently have Duo for Microsoft RDP set up and running for a client, and it's working fine, however we're running into an oddity when if a user tries to sign into Windows using the "Network Sign-In" option, it bypasses Duo entirely and doesn't prompt. The user is able to sign in as if they were in bypass mode.

I'm not sure if this is because that method has to be protected by Duo for Microsoft RRAS, or if it's a misconfiguration on my side. Any advice/help would be appreciated.

[bblair · Accepted solution]

Putting the solution to this after talking to Duo support. Since Network Sign-in bypasses local authentication and instead uses the VPN to authenticate into Windows, it bypasses Duo entirely. To protect both local Windows sign-in AND when using Network sign-in, you'd need to use both the Microsoft RDP and the Microsoft RRAS applications in this scenario.