Outdated client, Outdated server or Incompatible client errors
The player's game version and the server's version don't match. Join with the same version as the server, change the server version in the Versions tab, or add ViaVersion.
- Difficulty:
- Beginner
- Time:
- 5 minutes
On this page
Messages like Outdated client! Please use 1.21.4, Outdated server! I'm still on 1.20.1 or Incompatible client! Please use ... mean the player's Minecraft version is different from the server's. The version number in the message is the one the server runs. Make the versions match, or let other versions join with ViaVersion.
Why it happens
The player's launcher updated to the newest release, but the server is still on an older version.
The server was updated, but the player is still on an older version or an old modpack profile.
On Bedrock, phones and consoles update automatically, so players are often ahead of the server.
Fix 1: Join with the server's version (easiest)
On Java Edition, open the launcher, go to Installations, create a new installation with the server's version, and play with it. Check the server's version in the Versions tab (the top line shows, for example, "Currently running Paper · Installed Minecraft Version: 26.3") or in the server list.
Fix 2: Change the server's version
Make a backup in the Backups tab.
Open Versions, choose your software and the new version, and install it. Leave Wipe Server Files unticked to keep your world.
Check your plugins or mods support the new version before you start, and update them.
You don't need to change Java yourself: the Versions installer picks the right Java for the version you install. Only if you run a jar you uploaded yourself, set Java in Startup → Docker Image. See Change Java version.
Updating to a newer Minecraft version is fine, but going back to an older version is not supported. A world opened on a newer version may not load on an older one. Only roll back by restoring a backup from before the update. More in How to change Minecraft version or server software.
Fix 3: Let several versions join with ViaVersion
On Paper, Purpur or Spigot (or on a Velocity/BungeeCord proxy), these plugins let players on other versions join:
ViaVersion: newer clients can join an older server.
ViaBackwards (needs ViaVersion): older clients can join a newer server.
ViaRewind (needs both): very old clients such as 1.8.
Install them from Plugins → Browse Plugins (search the name, then Install) and restart. Some newer blocks and features may look different to players on other versions. Setup: ViaVersion: support older and newer clients.
ViaVersion does not work for modded servers (Forge, NeoForge). Modded players must use the exact same Minecraft and mod versions as the server. See Mod mismatch errors.
Bedrock players
Bedrock server: the server must run the same version as the players. When players update, update the server. Bedrock server types (Vanilla Bedrock, Nukkit, PocketmineMP) are not in the Versions tab; they are chosen through Settings → Change Egg. If you are not sure how to update yours, open a ticket and we will help.
Java server with Geyser: update Geyser (and Floodgate) when a new Bedrock version comes out. Geyser adds support for new Bedrock versions in its updates. See Geyser and Floodgate.
Frequently asked questions
Which version should my server run?
Pick the version most of your players use and that your important plugins or mods support. With ViaVersion you can then allow newer clients too.
The server list shows the server in red with a version number
That is the same version mismatch. Follow the fixes above.
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