@William For the error code,”0x8018000a)”, it means the device is already enrolled.
https://learn.microsoft.com/en-us/windows/win32/mdmreg/mdm-registration-constants
It seems a different user has already enrolled the device in Intune or joined the device to Azure AD. To determine whether this is the case, go to Settings > Accounts > Work Access. Look for a message that's similar to Another user on the system is already connected to a work or school. Please remove that work or school connection and try again.
Here are the steps to remove the other work or school account for the reference:
- Sign out of Windows, then sign in by using the other account that has enrolled or joined the device.
- Go to Settings > Accounts > Work Access, then remove the work or school account.
- Sign out of Windows, then sign in by using your account.
- Enroll the device in Intune or join the device to Azure AD.
Hope it can help
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