[SOLVED]Mod error while in .zip

So i made a basic mod today and basically, the mod works fine when launched in mcp, but it gives me an error.

Error code:

java.lang.ClassNotFoundException: rulerxx.mods.industriouspower.Industriouspower
at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:100)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at cpw.mods.fml.common.ModClassLoader.loadClass(ModClassLoader.java:57)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at cpw.mods.fml.common.FMLModContainer.constructMod(FMLModContainer.java:341)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventHandler.handleEvent(EventHandler.java:69)
at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)
at com.google.common.eventbus.EventBus.post(EventBus.java:268)
at cpw.mods.fml.common.LoadController.propogateStateMessage(LoadController.java:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at com.google.common.eventbus.EventHandler.handleEvent(EventHandler.java:69)
at com.google.common.eventbus.SynchronizedEventHandler.handleEvent(SynchronizedEventHandler.java:45)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:317)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:300)
at com.google.common.eventbus.EventBus.post(EventBus.java:268)
at cpw.mods.fml.common.LoadController.distributeStateMessage(LoadController.java:81)
at cpw.mods.fml.common.Loader.loadMods(Loader.java:442)
at cpw.mods.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:141)
at net.minecraft.client.Minecraft.a(Minecraft.java:405)
at net.minecraft.client.Minecraft.run(Minecraft.java:737)
at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.NullPointerException
at org.objectweb.asm.ClassReader.<init>(Unknown Source)
at cpw.mods.fml.common.asm.transformers.SideTransformer.transform(SideTransformer.java:27)
at cpw.mods.fml.relauncher.RelaunchClassLoader.runTransformers(RelaunchClassLoader.java:142)
at cpw.mods.fml.relauncher.RelaunchClassLoader.findClass(RelaunchClassLoader.java:93)

the mods files:

Industriouspower.java

package rulerxx.mods.industriouspower;
import net.minecraft.src.Block;
import net.minecraftforge.client.MinecraftForgeClient;
import cpw.mods.fml.common.Mod;
import cpw.mods.fml.common.Mod.Init;
import cpw.mods.fml.common.Mod.PreInit;
import cpw.mods.fml.common.event.FMLInitializationEvent;
import cpw.mods.fml.common.event.FMLPostInitializationEvent;
import cpw.mods.fml.common.event.FMLPreInitializationEvent;
import cpw.mods.fml.common.registry.GameRegistry;
import cpw.mods.fml.common.registry.LanguageRegistry;

@Mod(modid ="something", name = "Mod name lol", version = "1.3.2")
public class Industriouspower {

//Blocks
public static Block oreTin = new oreTin(204, 0).setHardness(2.5F).setStepSound(Block.soundWoodFootstep).setBlockName("oreTin");
public static Block testBlock = new testBlock(205, 1).setHardness(2.5F).setStepSound(Block.soundWoodFootstep).setBlockName("");
//WorldGen File
public static worldGen worldGen = new worldGen();
//Initialization
@Init
	public void loadMod(FMLInitializationEvent event) {
//Pre-Loading textures
 	MinecraftForgeClient.preloadTexture("/IP/textures/terrain.png");
//Blocks
 	GameRegistry.registerBlock(oreTin);
 	LanguageRegistry.addName(oreTin, "Tin Ore");
 	GameRegistry.registerBlock(testBlock);
 	LanguageRegistry.addName(testBlock, "RenderTest");
//WorldGen
 	GameRegistry.registerWorldGenerator(worldGen);
  
	}
}

oreTin.java

package rulerxx.mods.industriouspower;

import net.minecraft.src.Block;
import net.minecraft.src.CreativeTabs;
import net.minecraft.src.Material;


public class oreTin extends Block {
public oreTin(int i, int j) {
  super(i, j, Material.rock);
  this.setCreativeTab(CreativeTabs.tabTools);
}

public String getTextureFile() {
  return "/IP/textures/terrain.png";
} 
}

testBlock.java

package rulerxx.mods.industriouspower;

import net.minecraft.src.Block;
import net.minecraft.src.CreativeTabs;
import net.minecraft.src.Material;


public class testBlock extends Block {
public testBlock(int i, int j) {
  super(i, j, Material.rock);
  this.setCreativeTab(CreativeTabs.tabTools);
}

public String getTextureFile() {
  return "/IP/textures/terrain.png";
} 
}

worldGen.java

package rulerxx.mods.industriouspower;

import java.util.Random;

import net.minecraft.src.IChunkProvider;
import net.minecraft.src.World;
import cpw.mods.fml.common.IWorldGenerator;

public class worldGen implements IWorldGenerator { 

@Override
public void generate(Random random, int chunkX, int chunkZ, World world, IChunkProvider chunkGenerator, IChunkProvider chunkProvider) {
    world.setBlock(chunkX*16 + random.nextInt(16), 100, chunkZ*16 + random.nextInt(16), 204);
    // block X location, block Y location, block Z location, block id (in this case, wooden planks)
}
}
        

This code all works fine while running through eclipse, it just seems to give me errors while im running it through a multimc instance

ive got the mod.zip setup as

mod.zip - rulerxx - mods - industriouspower - .class files

            - IP - textures - terrain.png

Could someone please tell me what im doing wrong here?

EDIT -  Turns out recompiling and reobfuscating fixed the problem