ActivateTenant.cs

        static void ActivateTenant()
        {
            var insightApi = new InsightApiClient();
            string login = "MTAdmin";
            string password = "password";
            Guid sessionId = insightApi.Login(login, password, null, EApplicationType.Admin);
            string tenantId = "tenant_3";
            insightApi.ActivateTenant(sessionId, tenantId);
            TenantInfo[] tenants = insightApi.GetTenants(sessionId);
            var tenant3 = tenants.First(t => t.TenantId.Equals(tenantId, StringComparison.InvariantCultureIgnoreCase));
            Console.WriteLine(" Tenant Id: '{0}', Is Active: '{1}'", tenant3.TenantId, tenant3.IsActive);
        }