C#开发IOS推送服务端报错

最近，在开发IOS推送的服务端的时候，在sslStream.AuthenticateAsClient(host, certificates, System.Security.Authentication.SslProtocols.Ssl3, false);代码中，报：System.IO.IOException: Authentication failed because the remote party has closed the transport stream.
   at System.Net.Security.SslState.StartReadFrame(Byte[] buffer, Int32 readBytes, AsyncProtocolRequest asyncRequest)
   at System.Net.Security.SslState.StartReceiveBlob(Byte[] buffer, AsyncProtocolRequest asyncRequest)
   at System.Net.Security.SslState.CheckCompletionBeforeNextReceive(ProtocolToken message, AsyncProtocolRequest asyncRequest)
   at System.Net.Security.SslState.StartSendBlob(Byte[] incoming, Int32 count, AsyncProtocolRequest asyncRequest)
   at System.Net.Security.SslState.ForceAuthentication(Boolean receiveFirst, Byte[] buffer, AsyncProtocolRequest asyncRequest)
   at System.Net.Security.SslState.ProcessAuthentication(LazyAsyncResult lazyResult)
   at System.Net.Security.SslStream.AuthenticateAsClient(String targetHost, X509CertificateCollection clientCertificates, SslProtocols enabledSslProtocols, Boolean checkCertificateRevocation)
   at MoonAPNS.PushNotification.OpenSslStream(String host, X509CertificateCollection certificates) in E:\linxm\Sources\APNS-Test\APNS_Moon\PushNotification.cs:line 231
我试了JdSoft.Apple.Apns和MoonApns，都出现相同的错。
请问各位大侠有没有知道是什么原因，如何解决？