Symptoms: You can’t turn on network discovery in the Advanced Sharing Settings on Windows 7. When turned on, it reverts back to off ( it turns off ).
Reason: One of the reasons ( and the scope of this solution ) could be that the UPnP service is not running.
Solution: Start the service, here is how:
Go to the service manager. Click start and type services.mmc in the “Search programs and files”-box. Press enter. ( Ignore the ActiveX error / just click the ok button ) On the bottom of the window that you now see, click on the standard tab.
Make sure UPnP Device Host is started. If not start it by double clicking it.
In this “UPnP Device Host Properties” windows, make sure Startup type is set to Automatic, if it’s not, change it. Then click Start. Now click ok and close the Services windows.
Try again to Turn on network discovery.