@Yop Thanks for your explain.
I have done the test in my lab. It seems we can use DEM account to enroll the device during OOBE. The following are the steps as a reference:
1.Add a DEM account in intune portal.
2.Use the DEM account to login the device.
3.Check if the device is enrolled in intune. And I can see the device in intune portal.
Based on the test, I think we can use the DEM account to enroll devices during OOBE.
Hope it will help.
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