Can't disable Microsoft Store in Windows 10 Pro through Group Policy
Content provided by Microsoft
Applies to: Windows 10, version 1511
On a computer that's running Windows 10 Pro, you upgrade to version 1511 of Windows 10. After the upgrade, you notice that the following Group Policy settings to disable Microsoft Store are not applied, and you cannot disable Microsoft Store:
Computer Configuration>Administrative Templates>Windows Components>Store>Turn off the Store application
User Configuration>Administrative Templates>Windows Components>Store>Turn off the Store
This behavior is by design. In Windows 10 version 1511, these policies are applicable to users of the Enterprise and Education editions only.