Editing the GPO Settings
Now, the Goup Policy Objects have two components, the Computer Configuration that will apply to the computer objetcs and the User Configuration that will apply to the user objects. To accomplish our goal, we will need to make changes to both User and Computer Configuration.
The first thing we want to accomplish is to disable the sound on the client computer. Lucky for us there is a special setting under the User Configuration that will help us with that. Expand "Computer Configuration" > "Windows Settings" > "Security Settings" and go to the "System Services". On the right side you will see a list with the standard services present on the client computers. Find the "Windows Audio" service, double click it and mark the "Define this Policy Setting" and select the "Disabled" Startup option then press OK. Our first goal is now accomplished.
Next we need to remove the access to the Control Panel to any users affected by this GPO. We will go now to the User Configuration and expand "Policies" > "Administrative Templates" > "Control Panel" and select it. On the right side we can see the available settings. Select the "Prohibit access to the Control Panel" from the right side, right click and select "Edit".
On the left side select "Enabled" then click OK. All the users affected by this GPO are now restricted from accessing the Control Panel. The only thing remaining now it is to LINK this GPO to an Active Directory Organizational Unit (OU). An Organizational Unit is an Active Directory container into which you can place users, groups, computers, and other organizational units.
Go to Start > Administrative Tools > Active Directory Users and Computers. A new management console will open displaying your Active Directory structure. Expand the "mydomain.com" domain, select it, then right click and select "New" > "Organizational Unit". Name it "Test OU". You have now created a new OU where you can place the computers or users that should be affected by the new GPO. Go back to the Group Policy Management console and press F5 to refresh the configuration. The newly created OU will now appear under your domain. Select the "Test OU" right click it and select "Link an Existing GPO". Select the "Lock Down" GPO from the list and press OK.
In the same way you can create other Group Policy Objects and link them to your Organisational Units in the domain or to the whole domain in order to simplify your administrative tasks.