First let me say I was able to connect once but never again. I have also read the other posts here and none of them are similar to my situation.
My Surface Pro 3 sees the TV and pops up a message saying please follow the instructions on the TV. The TV pops up a message saying Connecting, but times out after a minute saying unable to connect. The TV has the latest firmware installed an I don't believe there is anything newer available for the Surface running Windows 8.1. I have removed the TV device from Windows several times, but nothing helps. The firewall is not the problem either. LG Support says, not the TV.
Anything else I can try. One thing I have noticed is that there was only a single time in which I was asked for a pin, I would have guessed deleting the device would have caused it to need to be entered again.