MDO query of EmailEvents is not accepted in the flow which is why causing the badgateway error

Hi Priya_elangovan​ ,

I do not think the problem is that EmailEvents itself is unsupported in Advanced Hunting. Microsoft’s current Advanced Hunting documentation still lists EmailEvents as one of the email and collaboration tables available in Defender XDR. (Microsoft Learn)

The more likely issue is the Power Automate side. The Microsoft Defender ATP connector does have an “Advanced Hunting” action, but it is the older connector and the action is just described as running a custom query, with dynamic output. Microsoft also notes that the older Advanced Hunting APIs are being replaced by the Microsoft Graph hunting APIs, and for Power Platform flows there is no built-in Graph Advanced Hunting action, so the recommended path is now a custom connector. (Microsoft Learn)

So if the query works in the Defender portal but returns BadGateway only from Power Automate, I would treat that as a connector/API limitation or flow execution issue rather than an EmailEvents table support issue. (Microsoft Learn)

A few things I would test:
Use a very small EmailEvents | take 10 query first.
Then add filters and projections gradually.
Also keep in mind the connector has throttling limits, and Advanced Hunting itself has query/result limits that can affect API execution differently from the portal. (Microsoft Learn)

If this is for production automation, I would strongly consider moving the flow to Microsoft Graph hunting via a custom connector instead of relying on the legacy Defender ATP Power Automate action. Microsoft’s guidance now points in that direction. (Microsoft Learn)

So my answer would be: yes, EmailEvents is supported in Advanced Hunting, but the BadGateway in Power Automate is most likely related to the legacy connector or query execution limits, not the table itself.