Launcher problems

MultiMC Fails to Launch: Not Enough Arguments (org.multimc.NotFoundException)

What the log looks like

org\.multimc\.NotFoundException
Not enough arguments\.\r?\norg\.multimc\.NotFoundException

How to fix it

  1. Connect to the internet and launch the instance using standard 'Launch' (not 'Launch Offline') at least once so MultiMC can download all required metadata, game libraries, and natives.
  2. Right-click the affected instance, click 'Edit Instance', open the 'Version' tab, and click 'Reload' on the right panel to force MultiMC to re-fetch corrupted or missing component metadata.
  3. If you migrated your setup from another computer, make sure you also copy the root 'meta' and 'libraries' folders alongside 'instances', or run the instance online to rebuild them.
  4. If you are on Linux and MultiMC cannot download version lists due to 'QSslSocket: cannot resolve' errors in MultiMC.0.log, install the matching OpenSSL compatibility libraries for your distro or update to a newer launcher build compiled against your system's OpenSSL version.
LoadersVanilla, Forge, Neoforge, Fabric, Quilt
SeverityStops the game
CategoryLauncher problems

Check your own log

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