错误

SocketException:尚无此类主机.

SocketException: No such host is known.

System.Net.Dns.hostent_to_IPHostEntry (System.String h_name, System.String[] h_aliases, System.String[] h_addrlist)

由于代理服务器而发生.我的IP位于代理服务器后面，在分配了直接Internet访问后，代码可以正常工作.

was occurring due to proxy server. My IP was behind a proxy server, after assigning the direct internet access the code is working fine.