I'm posting this here just in case, but my situation is such an edge case that I don't really expect a solution.
I'm using my android phone as a wifi hotspot, and my computer running the latest portable version of MB (3.4.7586 P) is connected to said hotspot. I'm also using the beta version (2.1) of MusicBee Wifi Sync.
My problem: after going through the wired sync, the android app can't locate the MB server. Looking at the error log, it seems the app is scanning the 0.0.0.XX IP range instead of 192.168.XX.XX, where my computer IP is located. If I use another phone as my wifi hotspot, and connect both my computer and my android phone as regular wifi clients, I can get the wifi sync to work as expected, so I don't think the problem comes from the firewall or Windows.
The reason why I'm still trying despite failing miserably each and every time is that I remember getting the wifi sync working once or twice despite the hotspot, but it happened several months ago and didn't last.
Anybody got an idea on how to solve this, or a way to manually input/override the computer IP in the android app?