diff --git a/test/E2ETests/compiler/shared/Mocks/StartupSocialTesting.cs b/test/E2ETests/compiler/shared/Mocks/StartupSocialTesting.cs
index 81dce18f5a..0bbf8c4cb4 100644
--- a/test/E2ETests/compiler/shared/Mocks/StartupSocialTesting.cs
+++ b/test/E2ETests/compiler/shared/Mocks/StartupSocialTesting.cs
@@ -119,9 +119,6 @@ namespace MusicStore
                 };
                 options.StateDataFormat = new CustomTwitterStateDataFormat();
                 options.BackchannelHttpHandler = new TwitterMockBackChannelHttpHandler();
-#if DNX451
-                options.BackchannelCertificateValidator = null;
-#endif
             });
 
             services.AddMicrosoftAccountAuthentication(options =>