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Fix "Outdated server!", "Outdated client!" and "Incompatible client!" in Minecraft

2 min readUpdated Nov 3, 2026

Why Minecraft says Outdated server, Outdated client or Incompatible client when you join, and how to fix it: match versions, change the server version, or add ViaVersion.

Depending on the Minecraft version, a player trying to join sees one of these:

Outdated server! I'm still on 1.20.4
Outdated client! Please use 1.21.4
Incompatible client! Please use 1.21.4

In the server list the server's version shows in red. It all means the same thing: the player's game version doesn't match the server's. Java Edition only lets a client join a server of the same protocol version.

1. Find both versions #

  • Server: near the top of the console after a start: Starting minecraft server version 1.21.4. The message in the player's error also tells you.
  • Player: the version on the Minecraft title screen (bottom left) or the installation they picked in the launcher.

"Outdated server" means the server is older than the player; "Outdated client" means the player is older. "Incompatible client" is the newer wording for both.

2. Quickest fix: the player matches the server #

  1. Open the Minecraft Launcher and go to Installations.
  2. Choose New installation, pick the server's version, and save.
  3. Press Play with that installation and join.

Modded clients (Fabric, Forge) must match the server's Minecraft version and its mods.

3. Let several versions join: ViaVersion #

On Paper or Purpur, these plugins translate between versions:

PluginLets in
ViaVersionNewer clients on an older server
ViaBackwards (needs ViaVersion)Older clients on a newer server
ViaRewind (needs both)Very old clients (1.7–1.8)

Download them from their official pages (Hangar or Modrinth), upload to plugins and restart. See installing plugins. On a network with a proxy (Velocity or BungeeCord), install them on the proxy. Players on a different version may see small differences, because new blocks and items don't exist on the older side.

4. Or change the server's version #

  1. Back up first (see backups). A world opened in a newer version can't safely go back to an older one.
  2. On Startup, set Minecraft Version to the version you want.
  3. Go to Settings and choose Reinstall Server, then start it. Full steps: startup settings.
  4. Update your plugins to versions made for the new Minecraft version. Newer Minecraft may also need a newer Java image on Startup.

Bedrock players (phones, consoles, Windows) #

Bedrock shows Outdated server! when Geyser is older than the player's game. Update Geyser to the newest build (and Floodgate with it), and ask players to update their game. Geyser follows the newest Bedrock release, so keep it updated. See Geyser + Floodgate setup.

FAQ #

Can I downgrade my server to an older version?

Not safely with the same world. Older versions can't read chunks saved by newer ones. Restore a backup from before the update, or start a new world.

Which version should my server run?

The newest version your important plugins support. Add ViaVersion so players on newer clients can still join.

ViaVersion is installed but players still can't join.

Make sure the Via plugins are up to date (they need updating for each new Minecraft release) and installed on the proxy if you have one.

Running your own Minecraft server? ESN Minecraft servers come with a live console, file manager, backups and schedules. See Minecraft plans · or ask in the ESN Systems Discord.

Still stuck? Use the live chat on the panel or ask in the ESN Systems Discord. Last updated November 3, 2026.