Launcher problems

HMCL Crash: NoClassDefFoundError in DefaultGameLauncher$$Lambda

What it looks like in the log

java.lang.NoClassDefFoundError: org/jackhuang/hmcl/core/launch/DefaultGameLauncher$$Lambda$1

How to fix it

  1. Force-close the frozen HMCL process using Windows Task Manager or your system's process manager.
  2. Delete your current HMCL 2.7.2.1 JAR or EXE file, as that specific build is corrupted.
  3. Download the latest stable release of HMCL from the official HMCL GitHub repository (HMCL-dev/HMCL) or website and place it in your Minecraft folder.
  4. Ensure Java 8 or newer is installed on your system before running the updated HMCL version.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityStops the game
CategoryLauncher problems

Check your own log

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