Disable WMC using Group Policy/Registry
Run GPEdit.msc (i.e. Group Policy Editor). Expand “Computer Configuration” if you wish to disable WMC for all user accounts on the computer. Expand “User Configuration” incase you wish to disable WMC only for the logged on user.
Next, Expand “Administrative Templates” and then “Windows Components”. Now choose “Windows Media Center”. Alter the setting for the option “Do not allow WMC to run” as “Enabled”.
Now that you have set the Windows Media Center disable policy, every time you try to run WMC, you will get a message informing you that the program cannot be opened due to software restriction policy.
How Can Home Premium Edition Users Disabe Windows Media Center
Home Premium edition users need to note that this edition does not include a Group Policy Editor (GPEdit.msc). Nevertheless, the policy that blocks WMC from running can be set in the registry manually.
To set policy registry key, you firstly need to open Registry Editor (command can be found here). Now locate the registry key mentioned below:
Then, right-click on “Microsoft”, select the option “New Key”. Name the key as “WindowsMediaCenter”. Within the registry branch “WindowsMediaCenter”, create new DWORD value and name it as “MediaCenter”. Set its value to 1.
As an alternate option login with the user ID which has admin rights. Go to command prompt by using CMD in run option and type the below mentioned command:
reg add HKLM\SOFTWARE\Policies\Microsoft\WindowsMediaCenter/v MediaCenter/t REG_DWORD/d 1/f
Incase, you wish to get back to re-launch WMC anytime in future. You simply need to delete the registry key named “WindowsMediaCenter” from the Registry Editor. As another option, you may run the below mentioned command in command prompt with elevated privileges.
reg delete HKLM\SOFTWARE\Policies\Microsoft\WindowsMediaCenter /v MediaCenter /f
Read the main post if you still are unable to disable Windows Media Player.