Launcher problems

Forge Crashes on Startup: Missing TByteObjectHashMap (trove4j Library)

What the log looks like

java\.lang\.NoClassDefFoundError:\s+gnu/trove/map/hash/TByteObjectHashMap
java\.lang\.ClassNotFoundException:\s+gnu\.trove\.map\.hash\.TByteObjectHashMap

How to fix it

  1. Use the official Minecraft Launcher or an established third-party launcher (such as Prism Launcher or MultiMC) that resolves all libraries defined in Forge's version JSON.
  2. Download the matching Forge Installer .jar from files.minecraftforge.net and run 'Install client' to repair and re-download missing files in your libraries folder.
  3. Check libraries/net/sf/trove4j/ inside your Minecraft directory to make sure the .jar file is present and not an empty file or an HTML error page; delete the net/sf/trove4j folder and reinstall Forge if it is corrupted.
  4. If you are building or configuring a custom launcher, ensure your classpath merges every entry from the Forge profile's libraries array onto the vanilla version classpath rather than loading only vanilla libraries.
LoadersForge
SeverityStops the game
CategoryLauncher problems

Check your own log

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