question

@aisecond-2443 It seems you have your own on-premises MDM server where you are trying to enroll your devices. Looking at the error message the service seems to be looking for the Terms Of use URL, can you confirm if you on-prem MDM server has a correct TOU URL. For Intune it is something like this :

@VipulSparsh-MSFT Thank you for your reply. If I set intunen's MDM discovery URL here, then this error will not occur. So this should be the wrong MDM discovery URL of our service. But how should we provide a url to register the device. We used to follow the documentation here.The URL provided by our service is https://uitest.safeuem.com/windows/Enrollmentserver/Discovery.svc
The response data is like this

We don’t know what went wrong. Howrad told us that we need to create a resource app and client app on Azure Active Direcroty to complete the verification process.
We want to develop our own MDM service to manage Windows 10 devices. Are there detailed development documents and operation guides to help us?

@aisecond-2443 Yes, we do have an article for adding an On-prem MDM app to Azure AD. You can have a look here

Let me know if you have any questions.

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