Hi @Henryk Bahr · Thank you for reaching out.
You can use NPS Extension to use Azure MFA for RDP connections as documented here: Integrate your Remote Desktop Gateway infrastructure using the Network Policy Server (NPS) extension and Azure AD
The only options you can use are Phone Call and App Notification. You cannot use the options where user is required to enter any code/otp/pin for MFA as during RDP connection, you don't get an option to enter the code/otp/pin.
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