System.IO.IOException：无法将数据写入传输连接：现有连接被远程主机强制关闭

Question

我一直在尝试使用 SSLstream 连接到服务器。 我有连接证书并且所有信用都是正确的。但不知怎的，它得到如下错误：

System.IO.IOException: Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host. --->   System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.Send(Byte[] buffer, Int32 offset, Int32 size, SocketFlags socketFlags)
at System.Net.Sockets.NetworkStream.Write(Byte[] buffer, Int32 offset, Int32 size)
--- End of inner exception stack trace ---
at System.Net.Sockets.NetworkStream.Write(Byte[] buffer, Int32 offset, Int32 size)
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 SslTcpClient.Open() in d:\Ishit\Fix\Webservice development - XML communication protocol\Work-by-Developer\ishit\EPP_Webservice\App_Code\SslTcpClient.cs:line 102
at EPP_Transaction_Webservice.Hello() in d:\Ishit\Fix\Webservice development - XML communication protocol\Work-by-Developer\ishit\EPP_Webservice\App_Code\EPP_Transaction_Webservice.cs:line 62

请帮我解决这个错误。 预先感谢。

Answer 1

我认为您可能需要检查您尝试连接的服务器是否已将您的 IP 列入黑名单/阻止。这看起来像是阻塞/拒绝通信的东西。当我的 sftp 服务器阻止我运行客户端的 IP 时，我遇到了类似的错误。 华泰 美联储

Answer 2

1. 检查连接加密类型：SSL3？ TLS10？ TLS11？ TLS12？ 为此，可以使用 Firefox > 页面信息 > 安全选项卡 > 技术详细信息
2. 添加以下行应用程序加载

System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls11 |安全协议类型.Tls12;

或

System.Net.ServicePointManager.SecurityProtocol = 默认值：System.Net.SecurityProtocolType.Ssl3 | System.Net.SecurityProtocolType.Tls;

注意：Tls11/Tls12 请求 .net >= v4.5 ??