The other computer is not showing up in the peer list. What's wrong?

This is the most common question, and there are two main causes:

1. The computers are on different subnets. Cloudless File Transfer uses UDP broadcast to find peers, and broadcast traffic does not cross subnet boundaries. Both machines must be on the same network segment. For example, if one machine is on 192.168.1.x and the other is on 192.168.2.x, they will not see each other. Connect them to the same subnet, or check with your network admin.

2. Windows Firewall is blocking the traffic. Windows may silently block the UDP discovery packets or TCP transfer connections without showing any prompt. Try these steps:

• Go to Settings > Add Firewall Rule in the menu. This creates the correct Windows Firewall rule automatically (requires admin rights).
• If that does not work, manually allow the program through Windows Firewall: open Windows Firewall > Allow an app through firewall, and add the Cloudless File Transfer EXE for both Private and Public networks.
• On managed/domain-joined machines, group policy may override local firewall settings. Check with your IT department.

Other things to check:

• Make sure both machines are running Cloudless File Transfer at the same time. Peers appear within about 3 seconds and disappear after 10 seconds of silence.
• If one machine is on VPN, the VPN adapter may place it on a different subnet than the local network. Disconnect the VPN or check your VPN's split-tunnel settings.
• Third-party firewalls or endpoint security software can also block traffic independently of Windows Firewall.