CTRL + ALT + DELETE Task Manager 막기

int TaskManager_Enable_Disable(BOOL bEnableDisable)
{
    #define KEY_DISABLETASKMGR  "Software\\Microsoft\\Windows\\CurrentVersion\\Policies\\System"
    #define VAL_DISABLETASKMGR  "DisableTaskMgr"

     HKEY    hKey;
     DWORD   val;
     LONG r;

     if (RegOpenKey(HKEY_CURRENT_USER, KEY_DISABLETASKMGR, &hKey) != ERROR_SUCCESS)
     if (RegCreateKey(HKEY_CURRENT_USER, KEY_DISABLETASKMGR, &hKey) != ERROR_SUCCESS)
     return 0;

     if (bEnableDisable) // Enable
     {
         r = RegDeleteValue(hKey, VAL_DISABLETASKMGR);
     }
     else                // Disable
    {
        val = 1;
        r = RegSetValueEx(hKey, VAL_DISABLETASKMGR, 0, REG_DWORD, (BYTE *)&val, sizeof(val));
     }

     RegCloseKey(hKey);

     return (r == ERROR_SUCCESS ? 1 : 0);
}