Hybrid Exchange Server setup and Windows Extended Protection?

Question

I'm currently running Exchange 2016 on-premise with Hybrid Setup to Exchange Online (AD DS --> Azure AD).

Based on https://microsoft.github.io/CSS-Exchange/Security/Extended-Protection/

How can I safely enable and secure the OnPremise Hybrid Exchange Server when the below script shows the warning:

Thank you,

Answer 1

You can check:
https://learn.microsoft.com/en-us/exchange/hybrid-deployment/hybrid-agent#checking-the-status-of-your-hybrid-agents

or:
https://learn.microsoft.com/en-us/exchange/hybrid-deployment/hybrid-agent#checking-the-status-of-your-hybrid-agents

If you dont see those options, its classic

Answer 2

Did you enable Modern Hybrid? If not and you are using classic Hybrid, then you are ok:
Extended Protection does not work with hybrid servers using Modern Hybrid configuration
Extended Protection cannot be enabled on Hybrid Servers which uses Modern Hybrid configuration. In Modern Hybrid configuration, Hybrid Server are published to Exchange Online via Hybrid Agent which proxies the Exchange Online call to Exchange Server.

Enabling Extended Protection on Hybrid servers using Modern Hybrid configuration will lead to disruption of hybrid features like mailbox migrations and Free/Busy. Hence, it is important to identify all the Hybrid Servers in the organization published via Hybrid Agent and not enable Extended Protection specifically on these servers.

https://learn.microsoft.com/en-us/exchange/hybrid-configuration-wizard-options