Windows Server2012 R2中对外请求https失败_windows the ssl connection could not be establishe

Windows 2012R2 The SSL connection could not be established ，这个破问题研究了好几天。

以下代码有个鸟用。

ServicePointManager.SecurityProtocol = SecurityProtocolType.Tls
           | SecurityProtocolType.Tls11
           | SecurityProtocolType.Tls12
           | SecurityProtocolType.Tls13;
            //设置最大连接数
            ServicePointManager.DefaultConnectionLimit = 200;
            //设置https验证方式
            ServicePointManager.Expect100Continue = true;     
 
            ServicePointManager.ServerCertificateValidationCallback =
            new RemoteCertificateValidationCallback(CheckValidationResult);

从老外论坛上查出来是服务器的问题，不得不升级了服务器到Windows Server2016。