Hi,
You have posted in the Microsoft Security Essentials forum, since your issue is related to SCCM / MECM I suggest you ask over at the dedicated SCCM / MECM Client deployment forum over here:
https://learn.microsoft.com/en-us/answers/topics/me-cm-site-deployment.html
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(If the reply was helpful please don't forget to accept as answer, thank you)
Best regards,
Leon