title: MS Surface Pro 3 runs BackgroundDownloader DownloadOperation perfectly on windows 8.1 but not starting after upgrading to windows 10
body: <p>I have an app using HttpClient to download text and using BackgroundDownloader to download relatively large files ex. pdf/jpg. </p>
  
  <p>We have 5 machines: two Toshiba PCs. a Asus T100. a MS Surface 3. and finally a MS Surface Pro 3. All of them run my app and download files perfectly on windows 8.1. </p>
  
  <p>However, a strange thing happens. After upgrading windows 10, former four of them run the same app charmingly. Only MS Surface Pro 3 run my app perfectly except BackgroundDownloader part. It works fine when using HttpClient download text file, but nothing happen when downloading large file. There are no exceptions (I use try-catch section to cover them) or any information disclosed. </p>
  
  <p>I have been reading posts <a href="https://stackoverflow.com/questions/31463770/windows-10-apps-downloadoperation-not-starting">windows 10 apps DownloadOperation not starting</a> but Status is Running and it won't download from the very first time. I have tried checking apps settings in"Allow a program to communicate through Windows Firewall", closing firewall, even Avira on that machine but all in vain. </p>
  
  <p>The most tragic thing is that MS Surface Pro 3 is my boss's computer. Could anyone have any ideas?</p>