I have 3 windows 10 pc's on a network. 2 pc's can see all 3 on network but 1 pc cant see 1 of the pc's on the network. this happens 1 every month or 2. All 3 pc's are connected via ethernet and all 3 are set to private network and all 3 are in the same workgroup. the pc that cant see the other pc can ping the ip of the missing pc in the list. why does it keep dropping it from the list?