According to this:
https://social.msdn.microsoft.com/Forums/windowsdesktop/en-US/c3d25ade-10c9-4404-92c4-a16ba202ae7b/wifi-proteceted-setupwps-implementation-in-native-wifi-driver-usb?forum=wdk
discusstion
Windows 7 will display WPS notification if
1. AP broadcast the beacon with WPS capability
2. if AP have WPS capability in the beacon, Windows 7 will start a WPS action, try to get M1 message from AP
3. Windows 7 will look at the M1 message, if config methods have Push Button support Windows 7 will show the WPS notification.
Troubleshooting:
if you have WPS informtaion in the beacon & push button support in the M1 message, but Windows 7 doesn't show up the WPS notification, there most be something wrong with the wireless driver, the wireless driver may not get the packet format correctly.
