Can't Connect to a Minecraft Server: Connection Errors and Fixes

1. “Failed to connect to the server”: Connection timed out or refused

This is the game's message when it doesn't even reach the server. The reason appears underneath: “Connection timed out” means nobody is answering; “Connection refused” means the machine answers but no server is listening on that port.

The usual causes, in order: the address is mistyped (a letter, a trailing space, a port that shouldn't be there), the server is off or starting (it takes one or two minutes to be ready after starting it), or the port isn't open.

If the server is on a friend's PC, it's almost always the last one: TCP port 25565 has to be forwarded on their router, and some ISPs (CG-NAT) don't allow it (how to play without port forwarding). On a rented server the port is already open: first check it's on. The “Is my Minecraft server online?” tool tells you from the outside, using the same address you use in the game.

2. “Incompatible client!” or “Outdated client”: a different version

Your Minecraft version isn't the server's. A server without plugins says “Incompatible client! Please use” followed by the version you need, whether yours is older or newer. A Paper server says “Outdated client! Please use…” if yours is older and “Outdated server! I'm still on…” if it's newer. In the “Multiplayer” list, that server shows its version in red.

Fix: in the launcher, “Installations” → “New installation” with the server's exact version, and join with it. If whoever runs it prefers everyone to join with their own version, on a Paper server you install ViaVersion (for newer versions) and ViaBackwards (for older ones): the ViaVersion guide explains it.

3. “Failed to verify username!” or “Invalid session”

Minecraft Java servers check your account with Mojang's servers. If those fail (it happens now and then), there's nothing to do but wait. Otherwise, do what the “Invalid session” message itself suggests: close the game and the launcher and open them again; if it persists, sign out of the launcher and sign back in with your account. That fixes almost every case.

Turning off that check (online-mode=false) to let unofficial accounts in isn't recommended: it lets anyone in with someone else's name, including an operator's.

4. “You are not white-listed on this server!”

The server has the whitelist turned on and your name isn't on it. On a Paper server the message reads “You are not whitelisted on this server!”. Ask the admin to type whitelist add YourName in the console, with the exact name of your Java account (the whitelist commands). Bedrock players who join through Floodgate are added with fwhitelist add.

If nobody can join a freshly set-up server, this is why: since 26.3, the whitelist comes turned on by default (the 26.3 guide covers it). On NapNodes it comes turned off.

5. Mismatched mods or stuck on “Loading terrain”

On a modded server you need the same mods and the same version in your game. The message usually says which one is missing or extra. The safest thing is to install the same modpack as the server (how your friends join a modpack server).

If it gets stuck on “Loading terrain” and then kicks you, check whether the same happens to everyone else: the server may be short on memory or generating world.

Other messages: server full, banned or kicked

“The server is full!”: as many people are already on as max-players allows. Whoever runs it raises it in server.properties (on NapNodes, “Settings” → “Max players”) and restarts. How many it really handles is another matter: it depends on the RAM and on what people are doing.

“You are banned from this server”: you have a ban. Only an admin can lift it, with pardon YourName (or pardon-ip if the ban is by IP). “Kicked by an operator” is a kick: you can join again.

“You logged in from another location”: someone has joined with your account, or your game got stuck inside. Wait a minute and try again.

If you get in fine but get kicked a while later, while playing (“Flying is not enabled on this server”, “You have been idle for too long!”, “Timed out”…), it's explained in why the Minecraft server kicks me.

How to tell whether the problem is yours or the server's

Ask another player whether they can join. If they can, the problem is your version, your account or your connection. If nobody can, check the panel: is it on? Are there errors in the console? With NapNodes you can see the status and the “Console” from panel.napnodes.com, and restart the server from there. If nobody can join because it never finishes starting, the console says why.

Frequently asked questions