Players Cannot Connect to Your Minecraft Server

Someone cannot get onto your server. Almost every case comes down to one of five things, and you can rule them out in a couple of minutes. Work through these in order rather than changing settings at random.

1Is the Server Actually Running?

• Log in to your game panel and open your Minecraft server.
• The status next to the server name should read RUNNING, and the console should end with Done and a startup time.
• If the console is stuck on Preparing spawn area, it is still starting. Give it a moment.
• If it keeps stopping and starting on its own, read the last lines of the console before the crash. That is where the reason is.

2Are They Using the Right Address?

• Copy the ADDRESS from the SERVER panel and give them exactly that, including the port.
• A missing port is the single most common cause. See how to connect to your Minecraft server.
• Test it yourself from your own machine. If you can join and they cannot, the problem is on their side, not the server.

3Do the Versions Match?

• Minecraft refuses connections between different versions, usually with an "Outdated client" or "Outdated server" message.
• The Versions page shows what your server runs. They need that exact version selected in their launcher.
• If you run a modpack, they need the same pack at the same version, not just the same Minecraft version.

4Is Something Blocking Them?

• Whitelist. If the whitelist is on, anyone not on it is refused. Check the Whitelist tab on the Players page and add them. See how to enable a whitelist.
• Bans. Check the Bans tab on the same page. A ban can be on the name or the IP.
• The server is full. max-players in server.properties sets the cap.

5Are They Using a Non Premium Account?

• A server in the default online mode only accepts genuine Minecraft accounts, and rejects cracked launchers with a message about not being authenticated.
• If your server is meant to accept them, see how to use a cracked client like tlauncher.
• Be aware of what that trades away. Anyone can then join as any username, including yours.

Good to Know

• A plugin can refuse connections too. If it started after you installed something, disable the newest plugin and restart. See how to install plugins.
• The error message is the fastest clue. "Outdated client" is a version problem, "You are not white-listed" is the whitelist, "Failed to authenticate" is the account type. Ask them to read out exactly what they see.
• One player or everyone? If only one person cannot join, it is their client, their version or their account. If nobody can, it is the server.

Finished

If you have worked through all five and players still cannot connect, open a ticket with your server address, the exact error your player sees, and what the console shows when they try.