Wrong mod loader

MixinPreProcessorException: Attach error calling FabricLoader on NeoForge or Forge

What it looks like in the log

org.spongepowered.asm.mixin.transformer.throwables.MixinPreProcessorException: Attach error for village_taverns.mixins.json:PotionsMixin from mod vill

How to fix it

  1. Open your crash report, scroll down to the 'Caused by: org.spongepowered.asm.mixin.transformer.throwables.MixinPreProcessorException' line, and read the mod ID right after 'from mod' (for example, village_taverns) instead of blaming the mod named at the very top of the log.
  2. Check that mod's jar in your mods folder to ensure you installed the NeoForge/Forge version for your Minecraft release rather than a Fabric jar.
  3. Update the offending mod (such as Village Taverns) to its latest NeoForge build where the leftover FabricLoader mixin reference is patched, or remove the mod from your mods folder if no fixed version is available yet.
  4. If you are intentionally trying to run Fabric mods on NeoForge, install Sinytra Connector alongside Forgified Fabric API, since Forgified Fabric API alone does not provide the FabricLoader class.
LoadersNeoforge, Forge
SeverityStops the game
CategoryWrong mod loader

Check your own log

Related errors

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