Outlook AddIn Mobile问题-在移动设备中不起作用，而相同的代码适用于桌面和Web客户端

Question

我在Microsoft Exchange Server服务中遇到了以下错误，但仅在移动设备上，因为相同的代码适用于台式机和网络。

错误消息：

  

System.Net.WebException：远程服务器返回错误：（401）   未经授权。

     

在System.Net.HttpWebRequest.GetResponse（）在   Microsoft.Exchange.WebServices.Data.EwsHttpWebRequest.Microsoft.Exchange.WebServices.Data.IEwsHttpWebRequest.GetResponse（）   在   \ REDMOND \ EXCHANGE \ BUILD \ E15 \ 15.00.0913.015 \ SOURCES \ sources \ dev \ EwsManagedApi \ src \ EwsManagedApi \ Core \ EwsHttpWebRequest.cs：line   

为113      

Microsoft.Exchange.WebServices.Data.ServiceRequestBase.GetEwsHttpWebResponse（IEwsHttpWebRequest   请求）   \ REDMOND \ EXCHANGE \ BUILD \ E15 \ 15.00.0913.015 \ SOURCES \ sources \ dev \ EwsManagedApi \ src \ EwsManagedApi \ Core \ Requests \ ServiceRequestBase.cs：   行821请求失败。

     

远程服务器返回错误：（401）未经授权。

代码片段：

// Create an ExchangeService object, set the credentials and the EWS URL.
ExchangeService exchangeService = new ExchangeService();
exchangeService.Credentials = new OAuthCredentials(attachmentToken);
exchangeService.Url = new Uri(ewsUrl);
exchangeService.UseDefaultCredentials = true;
exchangeService.PreAuthenticate = true;
try
{
var getAttachmentsResponse =exchangeService.GetAttachments(attachmentIds.ToArray(),null,new PropertySet(BasePropertySet.FirstClassProperties,ItemSchema.MimeContent));
}
catch (Exception ex)
{
var errMsg = ex.Message;
var errInnerException = ex.InnerException;
message += "Inner Exception :" + errInnerException;
}