Summary of the problem Pack crashes before even starting Pack Version Recommended What is the bug? When I click launch, the Minecraft window doesn't even open. Mod & Version No specific mod. Link to log file Minecraft doesn't even start when I click launch, so no log is generated. The launcher console says: SEVERE: Unhandled error launching minecraft java.lang.ClassNotFoundException: net.minecraft.client.Minecraft at java.net.URLClassLoader.findClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at java.lang.ClassLoader.loadClass(Unknown Source) at net.ftb.legacylaunch.Launch.main(Launch.java:85) Is it repeatable? Yes, I just click launch and it repeats. Known Fix None.