Prevent Crappy Launcher
Java mod listed for Minecraft 1.6–1.12. Downloads from the MC Java Mods app on Android.
⬇ Download on ModrinthA LaunchWrapper/ModLauncher CoreMod to prevent players from launching the game via a crappy launcher.
"Crappy Launcher" refers to a launcher that may cause performance and even compatibility problems that are extremely difficult to diagnose through debugging and other means, such as by messing with the game files and quietly adding JVM parameters for so called "optimization reasons".
Such a crappy launcher may also be a potential computer virus hazard, for example, calls system-level high risk libraries such as kernel32 for suspicious activities.
This mod plans to detect the crappy launchers exclusive to each OS by various methods, and throw exceptions when players try to launch the game using them.
To a certain extent, it could take care the confusion for modpack authors who need to solve potential problems that may be caused by launchers.
Only support Forge, no plans of Fabric port.
Use retro version for <= 1.12.2, modern version for >= 1.13.
Licensed under Mozilla Public License 2.0.
- Edition: Minecraft Java
- File type: .jar
- Minecraft versions listed: 1.6.4, 1.7.2, 1.7.3
- How to install: Install the matching mod loader (Forge, Fabric or NeoForge) for your Minecraft version. → Download the .jar. → Put it in the .minecraft/mods folder and launch that loader profile.
- Where to get it: Opens on Modrinth — not every file is mirrored on our own servers.
Install steps are the general flow for this file type — How to install Minecraft Java mods & modpacks walks through it step by step.
- Ships as PreventCrappyLauncher-2.1-retro.jar — drop this file into the mods folder
- Download size: 3 KB
- Download link checked 7 Oct 2026 — working
These come from our own check of the pack file, not from the source page.