Why won't Windows allow me to change a system setting?
If your computer is part of a network at an organization such as a school, government agency, or business, your organization's system administrator might have disabled or even removed certain settings by using Group Policy. Group Policy is a feature of Windows that lets system administrators manage users' access to Windows features. If you suspect that Group Policy is preventing you from changing a setting that you need to access, contact your system administrator.
If your computer isn't part of a network, a user with administrator privileges might have modified Group Policy on your computer to remove access to the settings. In this case, contact the administrator to modify the settings you'd like to change.
For more in-depth technical information about Group Policy, go to the Microsoft website for IT professionals.