我用http请求 老是提示这样的错误，是什么原因呢 ？

Message:An error occurred while sending the request.

Code:-2,StackTrace:

  at LNJyswxALXtU1MGZCJe.Js1NWexvZg6NT00hraq.K6mxbZK4BE(String  , String  , Dictionary`2  , String  , Int32  , String  ) in D:\Work\xbot-v5-uia\src\ShadowBot.UIAutomation.Provider\UIAutomation\Request\RestClientService.cs:line 40

  at ShadowBot.UIAutomation.Provider.Service.Request.HttpService.Send(String url, String method, Dictionary`2 headers, String body, Int32 connectTimeout, String saveFilename) in D:\Work\xbot-v5-uia\src\ShadowBot.UIAutomation.Provider\Service\Request\HttpService.cs:line 20

  at lambda_method19(Closure , k8qxV1b4PpcJXP7kDXp , Object[] )

  at sRHMsUbjx64dIDAgAYf.dG3WUNbq4Gx7QhRR58n.WKab68LKMw(k8qxV1b4PpcJXP7kDXp  , MLE4EeqSYAMVAZrosaQ  ) in D:\Work\xbot-v5-uia\src\ShadowBot.UIAutomation.Provider\Common\IPC\IPCActionInvoker.cs:line 63

  at SFTVKDbZuhy6rNZnKHe.gCq9PNbcOVEObh5k8uQ.ArvbQtVtAf(k8qxV1b4PpcJXP7kDXp  , e0LoPRqoTuxhdkArK9g  ) in D:\Work\xbot-v5-uia\src\ShadowBot.UIAutomation.Provider\Common\IPC\IPCActionInfo.cs:line 34

  at CQg1QsjLpob751TTBib.K6IQ1Sj4JOcgUbuCwAC.t6Mje6psNF(e0LoPRqoTuxhdkArK9g  ) in D:\Work\xbot-v5-uia\src\ShadowBot.UIAutomation.Provider\Common\IPC\IPCServiceInfo.cs:line 52