Why can't my friends join my Minecraft Java server?

Most likely it’s the whitelist. Since Minecraft 26.3, a new server starts with white-list=true, so only ops and the players you add can get in. Type whitelist add and your friend’s name into the live console and they’re in.

Add your friends to the whitelist

1. Open the live console in your Game Panel.
2. Type whitelist add and their Java account name: whitelist add Alex. They don’t need to be online.
3. Repeat for everyone else. whitelist list shows who’s on it.

From inside the game, ops at level 3 or higher can do the same with /whitelist add Alex. If you’re not an op yet, make yourself one first.

Ops can always join, whitelist or not. That’s why it often works for you and nobody else.

Turning it off, or making it stricter

• whitelist off lets anyone with the address in. whitelist on switches it back.
• To set it for good, change white-list in server.properties to false or true and restart your server from the Game Panel.
• enforce-whitelist=true kicks anyone already online who isn’t on the list when the whitelist reloads. It’s false by default.
• whitelist remove Alex takes someone off.

The list itself lives in whitelist.json, next to server.properties. If you edit that file by hand while the server’s running, type whitelist reload so it reads your changes.

The other usual causes

Their game is a different version

The server and every player need the same Minecraft version. Your friend will see one of these:

• Outdated client: the server is newer than their game. The message tells them which version to use.
• Outdated server: their game is newer than the server.

In the Minecraft Launcher, they can make a new installation in the Installations tab and pick the server’s version. On a modded server, everyone also needs the same mods at the same versions; see plugins or mods.

online-mode was switched off

Leave online-mode=true. It checks every player against Mojang’s accounts, and the Minecraft Wiki warns that with it off, people with fake accounts can join. Switching it off also changes how the whitelist matches players: it checks an offline ID made from their name, so friends you added while it was on stop matching.

They’re banned

A banned player sees “You are banned from this server”, and the ban wins over the whitelist. Check with banlist, then lift it with pardon Alex, or pardon-ip followed by the address for an IP ban.

They’re on Bedrock

A plain Java server doesn’t let in friends playing Bedrock Edition on phones, consoles or Windows. They need Geyser running on the server; the Minecraft page explains the options.

Something else

Check the address and port they typed match the ones in your Game Panel, and that max-players (20 by default) isn’t full. Still stuck? The AI assistant in your Game Panel can read your server’s console and logs with you, and it changes nothing until you approve.