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    Fix FiveM CURL, Handshake and License Errors

    Troubleshooting guide: CURL, Handshake, License Key issues

    You might encounter some common errors when running a FiveM server. This guide compiles solutions for the most frequent issues.

    1. 1
      Step 1

      CURL Error 56 / 28

      This indicates a connection failure to FiveM servers. Check internet connection, ensure Firewall isn't blocking, and try restarting the router/server.

    2. 2
      Step 2

      Handshake Failure

      Often caused by License Key issues or IP mismatch. Ensure the IP registered in Keymaster matches your actual server IP.

    3. 3
      Step 3

      Invalid License Key

      Ensure you copied the license key correctly into server.cfg (sv_licenseKey). Check for extra spaces.

    4. 4
      Step 4

      Could not bind to port

      Means the port is already in use. Ensure you aren't running two server instances, or change the port in server.cfg.

      # Windows: which process holds port 30120?
netstat -ano | findstr :30120

# Linux
ss -tulpn | grep 30120

    Helpful tips

    • Clear CacheMany strange issues are resolved by deleting the 'cache' folder inside your server data directory.
    • Update ServerAlways ensure you are using the latest 'artifacts' (server build files) to avoid outdated bugs.

    Frequently asked questions

    What does CURL error 28 mean on a FiveM server?

    Error 28 is a timeout: the server could not reach the Cfx.re services in time. Check that outbound HTTPS is allowed by the firewall, that DNS works on the machine, and that you run current server artifacts.

    Which ports does a FiveM server need?

    Port 30120 over both TCP and UDP for players, and port 40120 over TCP if you open txAdmin from outside. If you changed the endpoint in server.cfg, open that port instead.

    Players get stuck on handshake. What should I check first?

    Make sure UDP 30120 is open as well as TCP, that the endpoint lines in server.cfg use the same port, and ask the player to clear the FiveM cache before reconnecting.

    Why does my server say the license key is invalid?

    The key was typed with extra spaces, was revoked, or belongs to another server. Copy it again from Keymaster into the sv_licenseKey line, or generate a new key and restart the server.

    Run this guide on a ready server

    Need a server for this guide? FiveM server hosting from SNG comes with txAdmin, OneSync and DDoS protection, and the SNG CDN for FiveM delivers your server files to players from inside Saudi Arabia.

    Related FiveM guides

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