🎮 Game Error Codes What it means & how to fix it

Unturned Can't Connect to a Server? Here's the Fix

When Unturned can't connect — the invite times out, your dedicated server won't show in the list, or you get kicked on join — it's almost always a port-forwarding gap, a Steam/version mismatch, or a curated-vs-vanilla server filter. Work top to bottom.

Exact details for Unturned

Ports to forward (UDP)
27015 (game) + 27016 (query) + 27017 — forward the port and the two above it
Set server port
-port 27015 launch argument (keeps it fixed across restarts)
Protocol
UDP only — you do not need to forward TCP
Common cause of 'can't connect'
Only the base port opened — the query port +1 above must also be open or the server won't list

Error codes

Timed out / can't reach server The client never establishes a session with the host

Cause: Ports not forwarded, or only the base port opened.

Fix:
  1. Forward the connecting port AND the two above it — e.g. 27015, 27016 and 27017 (UDP).
  2. Set the server port with the -port launch argument so it stays fixed.
  3. Allow Unturned/Unturned_Server through Windows Firewall (Private + Public).
  4. Use a wired connection and restart the router to refresh NAT.
Server not in list / can't refresh The lobby browser can't see or query your server

Cause: Query port blocked or Steam master-list sync issue.

Fix:
  1. Open all three consecutive UDP ports — the query port is one above the game port.
  2. Add the server via Favorites using public IP:port if it won't appear in the browser.
  3. Log out of Steam and back in, then relaunch.
  4. Check that the server is set to your intended map/mode filter (curated vs vanilla).
Kicked: version / plugin mismatch Client and host builds don't match

Cause: One side updated, or has different Workshop mods/plugins.

Fix:
  1. Update Unturned on both machines to the same build.
  2. Subscribe to the exact Workshop items the server requires.
  3. Match RocketMod/OpenMod plugin sets if it's a modded server.
  4. Clear the Workshop download cache and re-verify game files.

Fixes that work for most Unturned errors

  1. Forward the game port plus the two ports above it (UDP) — e.g. 27015-27017.
  2. Fix the port with the -port launch argument.
  3. Allow Unturned through Windows Firewall (Private + Public).
  4. Add via Favorites by public IP:port if the server won't list.
  5. Match game version and Workshop items on both sides.
  6. Wired connection + router restart to refresh NAT.

FAQ

What ports does an Unturned server need?

By default 27015 and 27016, but you must also forward the port directly above the query port — so open 27015, 27016 and 27017 over UDP. Set the port explicitly with the -port launch argument so it never drifts.

Why won't my Unturned server show in the list?

Usually the query port (one above the game port) isn't forwarded, or the Steam master list is slow. Open all three consecutive UDP ports and, as a fallback, add the server via Favorites using your public IP and port.

Why do I get kicked the moment I join?

That's a version or plugin mismatch. Update both machines to the same Unturned build and subscribe to the exact Workshop items and RocketMod/OpenMod plugins the server runs.

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