Netgear Discovery tool 2.0.7.0 no longer finding my 5 switches.

I have used the utility many times before. Sometimes I have to run it twice to get results.  Now it doesn't find anything.  

I can ping them all by IP, I can get into them via web and they are all passing traffic. I have another MAC scanning utility that finds them all by MAC address just fine.  My Discovery tool version is 2.0.7.0 and I am running it as administrator. 

5 port in Computer Room GS105EV2
8 Port in dining room GS108EV4
8 Port in Basement GS108EV4
5 Port in Living Room GS105EV2
8 Port in Bedroom 108EV4

Any assistance in why they no longer respond to the Discovery tool would be much appreciated.  Thanks.