On computers running Windows Pro, a Group Policy rule can be used to block access to the classic Control Panel. This makes sense, for example, if you need to allow a less experienced user access to the machine and don’t want them to unwittingly stop something.
In the Run box, type: gpedit.msc and hit enter to open the Local Group Policy Editor. In the left column, click on User Configuration/Administrative Templates/Control Panel, then in the right pane, double-click on Control Panel and then on Disable access to Computer settings. Turn on the Enable button and click OK to approve the change. Attempts to open the Control Panel will then end with an error message about the administrator not having permission.