You needed to allow MC to communicate on Private Networks in Defender.
I posted that first image because that was the default, untouched settings when I added Media Center to the firewall.
I changed it in the second.
I don't know why "Public" would have been the default, but since that's how HDHomeRun configured itself, I went ahead and duplicated it for MC and added Domain & Private as well.
Also, you didn't need to have the Public Networks box ticked.
Good to hear, I'll remove it going forward!
MC is probably using the JRWeb.exe and JRWorker.exe as well.
Thanks, I went ahead and added those! They also defaulted to "public" only, so I reversed that to removing public and adding domain/private.
It didn't fix the issue
Have you Tamed Windows Defender?
I didn't, but it is configured now.
Though I didn't do individual files, just the folders.
Still getting that same error.