Server setup

Could not initialize class RenderSystem — a client mod is on the server

What the log looks like

could not initialize class [\w.]*blaze3d[\w.]*rendersystem
noclassdeffounderror[^\n]{0,60}blaze3d
noclassdeffounderror: *net/minecraft/client/

How to fix it

  1. Anything under net.minecraft.client or blaze3d only exists on the client
  2. Remove the client-only mod from the server mods folder
  3. Shaders, minimaps and HUD mods are the usual culprits
SeverityStops the game
CategoryServer setup

Check your own log

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