Wrong Minecraft version

Crash: ClassNotFoundException: net.irisshaders.iris.Iris

What it looks like in the log

java.lang.ClassNotFoundException: net.irisshaders.iris.Iris

How to fix it

  1. Update Iris Shaders in your mods folder to version 1.7.0 or newer (latest available for your Minecraft version).
  2. Update Sodium to a compatible version required by the new Iris release (for example, Sodium 0.5.8 or newer on Minecraft 1.20.1).
  3. Check the first line of the crash stacktrace right below NoClassDefFoundError (for example, net.mehvahdjukaar.moonlight for Moonlight Lib) and update that mod to its latest version as well.
  4. Remove any old duplicate Iris or Sodium .jar files from your mods folder before relaunching the game.
LoadersFabric, Quilt, Neoforge, Forge
SeverityStops the game
CategoryWrong Minecraft version

Check your own logDownload iris on 9Minecraft

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