Launcher problemsMultipleArgumentsForOptionException: Found multiple arguments for option gameDir
What it looks like in the log
joptsimple.MultipleArgumentsForOptionException: Found multiple arguments for option gameDir, but you asked for only one
How to fix it
- Check your launcher's profile settings under Custom Minecraft Arguments (or Extra Game Arguments) and remove any manually added `--gameDir` flags.
- If you use HMCL or a similar third-party launcher, open the version management settings for this instance to check if two Forge patches or duplicate OptiFine entries are installed on the same profile.
- Create a clean new instance for your Minecraft version, install Forge/NeoForge once, and avoid installing OptiFine via the standalone installer onto an already-modded launcher profile (place the OptiFine `.jar` in the `mods` folder instead, or use Embeddium/Oculus).
- Move your `mods`, `config`, and `saves` folders from the broken instance into the newly created instance directory, then update your launcher to its latest release.
| Loaders | Forge, Neoforge |
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| Severity | Stops the game |
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| Category | Launcher problems |
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Check your own log
