Hi Jason,
This should only be possible using GPO on a server. For Desktop O/S this is not possible.
There are a few things you could do though.
- Set up a new account for him and when signing in to an office product locally (e.g. Word or Excel) sign in to "This app only" it is an option which you will get upon the first time signing in, preventing you from enrolling in their tenant under their policies.
- Alternatively you could consider blocking websites through your router for his MAC address (as this is device bound)
Hope this helps!
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