Configure the Windows Phone 8.1 Emulator to work with Fiddler

2. Run Fiddler.
4. Run Fiddler and choose (from the menu) Tools, Fiddler Options ... Check these boxes in the HTTPS tab of the resulting dialog (and hit OK):
6. Click Tools > Fiddler Options > Connections . Change Fiddler Listen Port the from 8888 to something else, e.g. 8889 (The Windows Phone team decided to steal port 8888 for their debugger). Set these options in the Connections tab and then hit OK:
   
8. Set Proxy in the Gateway tab and then hits OK (This step was according the requirement. If required, then does this setting, El Se not):.
12. Click Ok button
14. In the quickexec box below Fiddler ' s session list, type prefs set fiddler.network.proxy.RegistrationHostName 169.254.80.80 where the IP address was found at the top of the too Ltip if hovering over the indicator at the Online top-right of Fiddler ' s toolbar.
16. Restart Fiddler.
18. Start VS. Load your project. Click for the Run Windows Phone 8.1 emulator .
20. Done.

Reference

Http://blogs.msdn.com/b/wsdevsol/archive/2013/06/05/configure-the-windows-phone-8-emulator-to-work-with-fiddler.aspx

Http://stackoverflow.com/questions/23462697/windows-phone-8-1-emulator-not-proxying-through-fiddler

Configure the Windows Phone 8.1 Emulator to work with Fiddler