Can't connect to a Minecraft server: every error and its fix

If you can’t connect to a Minecraft server, the cause is almost always one of four things: the address or port is wrong, the server is not running, your game version does not match, or the server is turning you away (whitelist, full server or an account check). The words on the error screen tell you which. Run the checklist, then jump to the section for your exact error.

Can’t connect to a Minecraft server: the one-minute checklist

1. Copy the address again. On Java Edition it is host or host:port, for example play.example.com:25570. You can leave the port out only when it is 25565, or when the domain’s SRV record supplies it. On Bedrock, the address and the port go in separate fields, and the default port is 19132.
2. Check that the server is running. Use the status checker in the next section, or ask the owner.
3. Match the version. When your version differs, the server’s entry in the multiplayer list shows the version it runs. As of October 2026, the current Java release is 26.3.
4. Match the edition. A Java player cannot join a Bedrock server. A Bedrock player can join a Java server only if it runs Geyser.
5. Restart the game and the launcher. This signs you in again.
6. Try a different network, such as a phone hotspot. A school or work network can block game traffic.

If you own the server, watch the console while your friend tries to join. A line with their name means they reached the server, and it gives the reason they were dropped. No line means the connection never arrived.

Test the server from outside with the status checker

Your own PC may reach the server over your home network while nobody else can. The Minecraft server status checker asks from outside, the way a friend’s game would.

1. Pick the edition: Java or Bedrock.
2. Type the address players use. Add :port only if the server does not use the default port.
3. Press Check server.

How to read the result:

• Online, but you can’t join. The server and its address are fine. Check your version and the whitelist, then find your error below.
• Offline. Nobody can get in. The server is stopped, the address or port is wrong, or a firewall or router is in the way. Only the owner can fix that.
• Offline, but people are playing. The owner may have hidden the status with enable-status=false in server.properties.

The checker refuses private addresses such as localhost and anything that starts with 192.168., because they only work inside your own network. If that is the address you gave your friends, they need your public address instead. A server that runs Geyser needs two checks, one for each edition.

Java Edition errors and what they mean

Most failed attempts show the heading “Failed to connect to the server” with a reason underneath. Find the reason below.

Connection refused

What it means. The reason contains “Connection refused”. The words after it vary with your system. The computer at that address answered, but no Minecraft server is listening on that port.

• Player: check the port number. If the server was started a moment ago, wait a minute and try again.
• Owner: make sure the server is running and has finished starting. The console prints a line that begins with Done when it is ready. Check that players have the port from your control panel, or the one in server-port. If the server stops by itself, see Minecraft server won’t start.

Connection timed out

What it means. The reason contains “Connection timed out”, or the screen just says “Timed out”. Nothing answered. The address leads nowhere, the machine is off, or a firewall or router dropped the request.

• Player: check the address for typos, turn off any VPN and try another network.
• Owner on a home PC: friends outside your home need your public IP address, and your router must forward TCP port 25565 to the PC that runs the server. The PC’s firewall must let Java through. See how to host a Minecraft server on your PC.
• Owner on a host: check that the server is started. A free Severoo server does not sleep when it is empty, but it is only online 24/7 as long as you renew it, so look at the renewal first. A server that is not renewed is suspended: re-enable it within 7 days, or it is removed permanently.

Unknown host

What it means. The game says “Unknown host”, and the server’s entry in the multiplayer list says “Can’t resolve hostname”. The name you typed could not be turned into an IP address.

• Player: type the address again. Remove spaces, http:// and any slash at the end.
• Owner: if you use your own domain, check its DNS records. A Java SRV record must be named _minecraft._tcp. followed by your domain, and its target must be a hostname, not an IP address. The status checker shows which IP address a name leads to.

Incompatible client, outdated client or outdated server

What it means. Your game version is not the server’s version. The wording depends on the server software. A vanilla 26.3 server says “Incompatible client! Please use 26.3”. Paper’s default messages are “Outdated client! Please use” and “Outdated server! I’m still on”, each followed by the server’s version.

• Player: start the game in the version named in the message. You choose it in the launcher before you press play.
• Owner: tell players which version to use, or update the server. On Paper, the ViaVersion plugin lets newer Java clients join an older server. Do not move the server down a version to suit one player: a world cannot be downgraded after a newer version has opened it.

Failed to verify username or invalid session

What it means. “Failed to verify username!” comes from the server. It asked Minecraft’s account service about you and got no confirmation. “Failed to log in: Invalid session (Try restarting your game and the launcher)” comes from your own game: its sign-in has expired.

• Player: close the game and the launcher completely, then sign in again. Use the official launcher with the account that owns the game. If the message says the authentication servers are down or not reachable, wait and try again.
• Owner: if other players can join, your server is fine. Keep online-mode=true. With it off, the server’s own startup warning says it “will make no attempt to authenticate usernames”, so anyone can join under any name, including yours. Mojang’s usage guidelines say server access “must only be granted to users who have a genuine paid-for version of Minecraft”. Bedrock players without a Java account join through Floodgate, with online mode left on.

You are not white-listed on this server

What it means. The whitelist is on and your name is not on it. Vanilla says “You are not white-listed on this server!”. Paper’s default is “You are not whitelisted on this server!”. Since 26.3, a new server has white-list=true by default, so a fresh server turns everyone away until names are added. That includes you, the owner, until you add or op yourself.

• Player: send the owner your exact username.
• Owner: type this in the console, with the player’s name in place of Steve:

whitelist add Steve

Run whitelist list to check. Operators are let in without being on the list. A Bedrock player who joins through Floodgate is added with fwhitelist add and their name. Geyser’s FAQ says that command only works for a player who has joined a Geyser server before. More in how to whitelist a Minecraft server.

The server is full

What it means. “The server is full!” appears when the number of players online has reached max-players, which is 20 by default.

• Player: wait for someone to leave.
• Owner: raise max-players in server.properties and restart. Every extra player uses memory, so check the RAM calculator first.

Connection reset

What it means. The message is usually “Internal Exception: java.net.SocketException: Connection reset”. The connection was open, then something cut it. The server stopped or crashed, or a router, firewall, VPN or weak Wi-Fi signal dropped it.

• Player: try again. If it keeps happening, restart your router, switch between Wi-Fi and mobile data, and turn off any VPN.
• Owner: if everyone dropped at the same moment, read the console from that moment for a crash or a restart. If it is one player, it is their connection. An overloaded server can also drop players: see how to reduce lag on a Minecraft server.

Bedrock Edition: unable to connect to world

Bedrock shows “Unable to connect to world.” for most failures. One message is clearer: “Could not connect: Outdated client!” means the game needs an update.

What the player can try

• Put the address and the port in their separate fields. The default Bedrock port is 19132, but a host may give the server a different one.
• Restart Minecraft. Geyser’s troubleshooting page says this sometimes fixes it, mostly on phones.
• On a console, expect extra steps: Geyser’s documentation says consoles join third-party servers “with workarounds”.

What the owner should check

• A Java server accepts Bedrock players only when Geyser is installed. See Minecraft Java and Bedrock crossplay.
• Bedrock uses UDP and Java uses TCP. A port that is opened or forwarded as TCP only does not work for Bedrock.
• If your host gives the server one port, Geyser has to use it. The setting clone-remote-port: true makes Geyser’s Bedrock port the same number as the Java port.
• Check the versions. As of October 2026, Geyser’s supported versions page lists Bedrock 26.30 to 26.52 and Java 26.2. A 26.3 Java server is not listed yet.
• Type geyser connectiontest, then your address and port, in the server console. The command comes from Geyser’s guide to this error.
• Run the status checker with Bedrock Edition selected.

What to send when you ask for help

Send the server owner, or the host’s support, these four things:

1. The exact words on the error screen.
2. The address and port you typed.
3. Your edition and game version.
4. What the status checker said.

Owners should add the console lines from the moment the player tried. If you have never joined a server before, start with how to join a Minecraft server.