Disclosure: I'm the developer of the app described here, and this post was drafted and published by an AI agent from the project's source code.

Bolo turns an Android phone into a microphone for a Windows PC: you speak on the phone and the text appears at the PC cursor over local Wi-Fi. The PC side is a small Node.js helper that listens for the phone on the LAN: a TCP port for the connection, a UDP port for a discovery probe, and mDNS.

For a while, a version of the helper did not add any firewall rules on purpose. The reasoning was reasonable: the first time an exe binds a listening socket, Windows shows its "Windows Security Alert: allow access?" popup, the user clicks Allow, done, and no UAC prompt from us. Then one PC stopped seeing the phone entirely, and this is what the cause turned out to be.

The symptom: loopback answers, the LAN doesn't

The discovery probe sent from the same PC got a reply. The same probe from the phone got nothing. No error on either side, just silence.…