Hi @Aondio_Carlo,
I think using a group policy in this case may not be the best solution for you. When your Meraki MX picks up each login/authentication event and sees an individual user, I believe it is then applying the appropriate group policy to the device (or client) and not each unique session id within the OS. Since they are all accessing one physical network device, it will apply one group policy to the client at a time. You may need to find a different solution for limiting access with that specific RDP host.
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