DLP policy stops working when device is joined to the local domain

Hello Rime_Razgallah,

Hope you’ve already been able to get this sorted. If not, here’s a quick clarification that may help based on recent deployment observations.

Endpoint DLP requires the device to be Entra joined or Entra hybrid joined or Entra registered. In case, the device is joined only to local domain and not Entra or not registered with Entra, then endpoint DLP might not work as expected. Refer to the prerequisites for onboarding here: 

https://learn.microsoft.com/en-us/purview/device-onboarding-overview#prepare-your-windows-devices 

Hope this helps!

Please mark as solution, if you find the answer helpful. This will assist others in the community who encounter a similar issue, enabling them to quickly find the solution and benefit from the guidance provided.