Lately (maybe since last month), I’ve had that
Music.UI.exe executable, located in
C:\Program Files\WindowsApps\Microsoft.ZuneMusic_3.6.19261.0_x64__8wekyb3d8bbwe, regularly (like, every few hours) popping up in my firewall, trying to access the network 😮 Every time, I denied it and killed it, but it kept coming back.
I tried deleting the file, with no success (permission denied, even as admin).
I eventually found the solution: go to Settings > Privacy > Background Apps, and turn off Groove Music. While you’re at it, you might want to disable the shitload of other apps that are there too.