Launcher problems

HMCL Crash: DefaultGameLauncher$$Lambda$1 ClassNotFoundException

What it looks like in the log

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

How to fix it

  1. If the HMCL window becomes unresponsive after clicking OK on the error popup, force-close the launcher using Windows Task Manager or your system process monitor.
  2. Delete the broken HMCL 2.7.2.1 `.exe` or `.jar` launcher file from your computer.
  3. Download the latest stable release of HMCL from the official GitHub repository (`github.com/HMCL-dev/HMCL/releases`) or official website (`hmcl.huangyuhui.net`).
  4. Move the new HMCL file into your game folder and run it to launch your existing `.minecraft` installations normally.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityStops the game
CategoryLauncher problems

Check your own log

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