Authentication failed because remote party has closed the transport stream

I am developing a TCP client to connect OpenSSL server with the certificate authentication. I have using .crt and .key files shared by server team. These certificates are generated by OpenSSL commands.

I am using SslStream object to authenticate the Tcp client by calling SslStream.AuthenticateAsClient method by passing server IP, SslProtocols.Ssl3 and X509CertificateCollection.

I am getting the following error:

Authentication failed because the remote party has closed the transport stream

I would advise against restricting the SecurityProtocol to TLS 1.1.

The recommended solution is to use

System.Net.ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls12 | SecurityProtocolType.Tls11 | SecurityProtocolType.Tls;

Another option is add the following Registry key:

Key: HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319 
Value: SchUseStrongCrypto 

It is worth noting that .NET 4.6 will use the correct protocol by default and does not require either solution.

If you want to use an older version of .net, create your own flag and cast it.

    //
    // Summary:
    //     Specifies the security protocols that are supported by the Schannel security
    //     package.
    [Flags]
    private enum MySecurityProtocolType
    {
        //
        // Summary:
        //     Specifies the Secure Socket Layer (SSL) 3.0 security protocol.
        Ssl3 = 48,
        //
        // Summary:
        //     Specifies the Transport Layer Security (TLS) 1.0 security protocol.
        Tls = 192,
        //
        // Summary:
        //     Specifies the Transport Layer Security (TLS) 1.1 security protocol.
        Tls11 = 768,
        //
        // Summary:
        //     Specifies the Transport Layer Security (TLS) 1.2 security protocol.
        Tls12 = 3072
    }
    public Session()
    {
        System.Net.ServicePointManager.SecurityProtocol = (SecurityProtocolType)(MySecurityProtocolType.Tls12 | MySecurityProtocolType.Tls11 | MySecurityProtocolType.Tls);
    }