c＃ - Exchange Web Service API和401未经授权的例外

以下EWS调用偶尔会生成处理401错误（1000封电子邮件中的1封） .

emailMessage.Load（propertySet）; emailMessage.Move（WellKnownFolderName.DeletedItems）;

关于问题是什么的任何想法？电子邮件驻留在InBox中并受到许多规则扫描（由于驻留在InBox中），但规则并未将其从InBox中删除 . 稍后对同一电子邮件的重新处理将成功 . 凭证或propertySet没有问题，它只有静态引用 . 就好像，emailMessage虽然从service.FindItems（）中检索到，但却具有暂时的权限 . 我没有在EWS日志中看到任何相应的错误 .

为了澄清，应用于收件箱的规则正在移动其他电子邮件 . 严格来说，我不知道ES（消息实验室）在将电子邮件放入收件箱之前是否应用了规则（例如 Span 检查等） . 如果在插入后应用，我可以理解可能有2个进程对InBox起作用，可能同时进行 . 如果是这样，我不知道其含义可能是什么 . 这都是猜测工作 - 我不知道这是否与我的问题有关 . 但是，异常表明401是由EWS响应引起的，即使我在EWS日志中没有找到相同的内容 .

Error: Microsoft.Exchange.WebServices.Data.ServiceRequestException: The request failed. The remote server returned an error: (401) Unauthorized. ---> System.Net.WebException: The remote server returned an error: (401) Unauthorized.
   at System.Net.HttpWebRequest.GetResponse()
   at Microsoft.Exchange.WebServices.Data.EwsHttpWebRequest.Microsoft.Exchange.WebServices.Data.IEwsHttpWebRequest.GetResponse()
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse(IEwsHttpWebRequest request)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse(IEwsHttpWebRequest request)
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ValidateAndEmitRequest(IEwsHttpWebRequest& request)
   at Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest`1.Execute()
   at Microsoft.Exchange.WebServices.Data.ExchangeService.InternalLoadPropertiesForItems(IEnumerable`1 items, PropertySet propertySet, ServiceErrorHandling errorHandling)
   at Microsoft.Exchange.WebServices.Data.Item.InternalLoad(PropertySet propertySet)

Microsoft.Exchange.WebServices.Data.ServiceRequestException: The request failed. The remote server returned an error: (401) Unauthorized. ---> System.Net.WebException: The remote server returned an error: (401) Unauthorized.
   at System.Net.HttpWebRequest.GetResponse()
   at Microsoft.Exchange.WebServices.Data.EwsHttpWebRequest.Microsoft.Exchange.WebServices.Data.IEwsHttpWebRequest.GetResponse()
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse(IEwsHttpWebRequest request)
   --- End of inner exception stack trace ---
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse(IEwsHttpWebRequest request)
   at Microsoft.Exchange.WebServices.Data.ServiceRequestBase.ValidateAndEmitRequest(IEwsHttpWebRequest& request)
   at Microsoft.Exchange.WebServices.Data.MultiResponseServiceRequest`1.Execute()
   at Microsoft.Exchange.WebServices.Data.ExchangeService.InternalMoveItems(IEnumerable`1 itemIds, FolderId destinationFolderId, Nullable`1 returnNewItemIds, ServiceErrorHandling errorHandling)
   at Microsoft.Exchange.WebServices.Data.ExchangeService.MoveItem(ItemId itemId, FolderId destinationFolderId)
   at Microsoft.Exchange.WebServices.Data.Item.Move(FolderId destinationFolderId)
   at Microsoft.Exchange.WebServices.Data.Item.Move(WellKnownFolderName destinationFolderName)