/// <summary>
        /// Add a service key.
        /// </summary>
        private static void AddServiceKey(string displayName, byte[] keyValue, string protectionPassword, ServiceKeyType keyType, ServiceKeyUsage keyUsage)
        {
            ManagementService svc = ManagementServiceHelper.CreateManagementServiceClient();

            UTF8Encoding enc = new UTF8Encoding();

            ServiceKey serviceKey = new ServiceKey()
            {
                DisplayName = displayName,
                Type        = keyType.ToString(),
                Usage       = keyUsage.ToString(),
                Value       = keyValue,
                Password    = string.IsNullOrEmpty(protectionPassword) ? null : enc.GetBytes(protectionPassword),
                StartDate   = defaultStartTime,
                EndDate     = defaultEndTime
            };

            svc.AddToServiceKeys(serviceKey);
            svc.SaveChangesBatch();
        }
        /// <summary>
        /// Update the service key value and the protection password.
        /// </summary>
        private static void UpdateServiceKey(string displayName, byte[] keyValue, string protectionPassword, ServiceKeyType keyType)
        {
            UTF8Encoding      enc = new UTF8Encoding();
            ManagementService svc = ManagementServiceHelper.CreateManagementServiceClient();

            ServiceKey serviceKey = svc.ServiceKeys.Where(sk => sk.DisplayName == displayName && sk.Type == keyType.ToString()).First();

            serviceKey.Value    = keyValue;
            serviceKey.Password = string.IsNullOrEmpty(protectionPassword) ? null : enc.GetBytes(protectionPassword);

            svc.UpdateObject(serviceKey);
            svc.SaveChangesBatch();
        }