Lets get started :
1 – On your Server 2012, open Group Policy Management look for Group Policy Objects.
2 – Next, right click Group Policy Objects and click New.. in the New GPO box, you can key in any GP name you prefer, for this demo I use CPX Control Panel Policies.
3 – Then you have to right click the new GPO ( CPX Control Panel Policies) you just created and click Edit..
4 – on the Group Policy Management Editor, scroll to User Configuration, Policies, Administrative Templates , Control Panel.. and on the right pane, you will see setting call Prohibit access to Control Panel and PC setting and double click on that setting.
5 – on the Prohibit access to Control Panel and PC setting box, Click Enabled so that you will disable all Control Panel function and then click OK..
6 – once you click OK, right click on the desire OU that you want this particular setting to be affected and click Link an Existing GPO… For this demo, I choose my Sales OU (so that all users in Sales OU couldn't open their Windows Control Panel).
7 – on the Select GPO box, choose CPX Control Panel Policies and click OK.
8 – now you can verify that under Sales OU, there is CPX Control Panel Policies attached.
9 – next, log in as a Sales user in Windows 8 client system (for this demo I use Dan as my user, Dan is Sales user).
10 – once you successfully log in to Windows 8 client, open Command Prompt and type gpupdate /force to retrieve and update the policy from Domain.11 – Next, on Windows 8 try open Control Panel and you will get an Restrictions warning.