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Connection Troubleshooting

If RSClient can't reach RSServer, work through these checks in order. Each one eliminates a category of problem.

1. Confirm the server TCP port​

On the server machine, open Tools → Preferences and check the Server TCP port value.

  • Port 0 (the default) means networking is disabled — the server won't accept any connections. Set it to a port in the range 1024–65535.
  • Pick a port that isn't already in use. A common mistake is reusing the port assigned to MyLaps or ChronoTrack, which creates a TCP conflict. A common convention is to pick something above 30,000. Verify the port is free before assigning it:
    • Command Prompt: netstat -ano | find "33000" — a LISTENING line means it's taken.
    • PowerShell: Get-NetTCPConnection -LocalPort 33000 — errors out if nothing is listening, meaning the port is free.
    • Or use TCPView for a GUI view of everything currently listening.
  • After changing the port, restart RSServer for it to take effect.

On the client machine, make sure Tools → Preferences → TCP Server address and TCP Server port match the server's IP/hostname and port.

2. Test with tcping​

tcping is a free utility that tests whether a specific TCP port is reachable. It is more useful than plain ping because ping only tests basic network connectivity (ICMP). tcping tests whether the actual port is open.

Place tcping.exe in your Windows\System32 directory, then open a command prompt on the client machine:

tcping mydesktop 33000

Replace mydesktop with the server's hostname or IP address, and 33000 with the actual port. tcping reports whether the port is reachable and how long the round-trip takes.

3. Check firewalls​

Firewall rules are the most common cause of blocked connections. You need exceptions on every machine — server and clients alike.

Windows Firewall​

Add exceptions for both executables (RSServer.exe and RSClient.exe) and for the TCP port or a range of ports.

caution

Do this even if the Windows Firewall shows as "off" — Windows can still block ports when the firewall is nominally disabled.

Third-party firewalls​

If the machine runs McAfee, ZoneAlarm, Norton, or any other security suite, add the same exceptions there. These products often have their own firewall independent of the Windows one.

4. Ping the server​

From the client machine, try a basic ping:

ping 192.168.0.198

or by hostname:

ping mydesktop
OutcomeWhat it means
Ping succeedsBasic network connectivity is fine — the problem is likely a port/firewall issue. Go back to steps 1–3.
Ping failsThe machines can't reach each other at all. Check cables, Wi-Fi, subnet configuration, or whether the hostname resolves correctly.

5. Version mismatch​

If the connection starts but you see an error about mismatched versions:

ConditionResult
Versions differ in any way (e.g. 9.0.1 vs. 9.0.3, or different build dates)Error — connection refused. Update the older side so both run the same build.
Versions match exactlyClean connection, no message.

The server compares the full version-and-date string. Even a patch-level or build-date difference blocks the connection — there is no warning-only mode.

Verify before race day

Copy the latest RSClient installer to every client machine well before the event. Verify connections from all machines while you still have time to troubleshoot.

See also​