We are having a very strange problem. Over Ethernet and USB, everything works fine. But, when we connect to our FRC robot over wi-fi, the driver station (and SmartDashboard and web dashboard) do not connect to the robot unless the laptop has just been rebooted. If I ping roborio-3128-frc.local, it does not find the host. The driver station is a Lenovo Thinkpad T430, and these problems started summer 2016, around the time that the driver station upgraded itself to Windows 10.
At that point, we figured out that connecting an ethernet cable to the robot, connecting wifi, and then disconnecting the ethernet allowed us to connect normally. I figured that the problem was the Windows 10 upgrade, so I clean installed Windows 8 on the computer and put in a new SSD. That made it reboot faster, but the connection problems didn't go away. Then, when I upgraded the driver station to the 2017 update suite, the Ethernet workaround stopped working.
I also tend to see the error "The mDNS service is slow to respond. Check firewall settings" in the driver station. I turned off the Windows firewall, and it did not solve the problem.
I also tried restarting certain NI network services, turning wifi on and off, and disabling every network interface but wifi. Neither thing helped. I can only connect to the robot if it is the first network that the laptop connects to after booting up (though strangely, I can connect to another network, disconnect as quickly as possible, then connect to the robot, and it does work).
This error happens across at least three different robots (all of the ones we've tested), and occurs with the 2016 and 2017 wireless bridge. I didn't test the older D-Link one.
It smells to me like there's something interfering with NI's mDNS service, or possibly the bridge is configured wrong somehow? What could be causing this error? Why would it persist across Windows reinstalls? Could it be some kind of network driver update that got pushed last summer?