Corrupted files

Unable to Launch: ClassNotFoundException FMLTweaker

What the log looks like

java\.lang\.ClassNotFoundException: cpw\.mods\.fml\.common\.launcher\.FMLTweaker

How to fix it

  1. Open your launcher's root directory (such as `.minecraft` or `MultiMC`), navigate to `libraries/net/minecraftforge/forge/`, and delete the folder matching your Forge version.
  2. If you use the official Minecraft Launcher, re-download the Forge 1.7.10 Installer JAR from files.minecraftforge.net and run 'Install client' again to regenerate the missing library files.
  3. If you use a third-party launcher like MultiMC, Prism Launcher, or HMCL, do not use the standalone Forge installer; instead, edit the instance, remove Forge under the Version settings, and install Forge using the launcher's built-in 'Install Forge' button.
  4. Check the full folder path to your launcher and Minecraft instance and remove any exclamation marks (`!`) from folder names, as Java cannot load `FMLTweaker` from paths containing `!`.
LoadersForge
SeverityStops the game
CategoryCorrupted files

Check your own log

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