服务器无法进行推送了，求帮忙解决一下问题

前几天突然发现服务器无法进行推送了（在此之前服务器没有做过任何修改，也没有安装其他任何软件）。节后进行调试发现换在其他服务器上面或者本地电脑上就能够进行推送。但是放在原服务器上面就无法实现了。一下是错误提示，求大神帮忙看看问题所在，需要如何来解决呢：
cn.jpush.api包提示错误

cn.jpush.api.common.resp.APIConnectionException: The underlying connection was closed: An unexpected error occurred on a send.
   at cn.jpush.api.common.BaseHttpClient.sendRequest(String method, String url, String auth, String reqParams) in h:\cn.jpush.api\common\BaseHttpClient.cs:line 141
   at cn.jpush.api.common.BaseHttpClient.sendPost(String url, String auth, String reqParams) in h:\cn.jpush.api\common\BaseHttpClient.cs:line 32
   at cn.jpush.api.push.PushClient.sendPush(String payloadString) in h:\cn.jpush.api\push\PushClient.cs:line 40
   at cn.jpush.api.push.PushClient.sendPush(PushPayload payload) in h:\cn.jpush.api\push\PushClient.cs:line 32
   at cn.jpush.api.JPushClient.SendPush(PushPayload payload) in h:\cn.jpush.api\JPushClient.cs:line 50
   at AppDataProvide_pushData.BLL.PushHelper.PushMsg(MSG_detail_beginSendMsg item) in h:\AppDataProvide_pushData.BLL\PushHelper.cs:line 41