arduino yun rev 2, ide 1.8.8 loses wifi ports in tools->port

running Windows 10 64bit, IDE 1.8.8.
2 x yuns on network.

I have had trouble for a while that after you upload a sketch to either yun the IDE loses the entry for the yuns in tools->port. The yuns are still accessible via browser, putty or winsct. Most of the time a restart of the computer (not yun) fixes the problem. Both yuns have had their firmware updated to the latest version. The only way to reliably upload sketches is to use usb. This is most frustrating and I am out of ideas any help you could give would be appreciated.