Hello i am new to modding but recently i have been learning how to code some basic items in minecraft. i got my mod working within the eclipse client (and server) but when i compiled my mod it no longer worked i will attach some of the files and the crash-report if anyone can help me. BTW the mod is for 1.8.9-forge-11.15.0.1708

crash-report:

---- Minecraft Crash Report ----
// Oh - I know what I did wrong!

Time: 13/02/16 3:19 PM
Description: There was a severe problem during mod loading that has caused the game to fail

net.minecraftforge.fml.common.LoaderException: java.lang.NoClassDefFoundError: coco12345678910/TheCoconutMod/Blocks/BlockTest
at net.minecraftforge.fml.common.LoadController.transition(LoadController.java:162)
at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:559)
at net.minecraftforge.fml.client.FMLClientHandler.beginMinecraftLoading(FMLClientHandler.java:240)
at net.minecraft.client.Minecraft.func_71384_a(Minecraft.java:417)
at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:329)
at net.minecraft.client.main.Main.main(SourceFile:124)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at net.minecraft.launchwrapper.Launch.launch(Launch.java:135)
at net.minecraft.launchwrapper.Launch.main(Launch.java:28)
Caused by: java.lang.NoClassDefFoundError: coco12345678910/TheCoconutMod/Blocks/BlockTest
at coco12345678910.TheCoconutMod.init.TheCoconutModBlocks.init(TheCoconutModBlocks.java:20)
at coco12345678910.TheCoconutMod.TheCoconutMod.preInit(TheCoconutMod.java:26)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at net.minecraftforge.fml.common.FMLModContainer.handleModStateEvent(FMLModContainer.java:560)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at net.minecraftforge.fml.common.LoadController.sendEventToModContainer(LoadController.java:211)
at net.minecraftforge.fml.common.LoadController.propogateStateMessage(LoadController.java:189)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.google.common.eventbus.EventSubscriber.handleEvent(EventSubscriber.java:74)
at com.google.common.eventbus.SynchronizedEventSubscriber.handleEvent(SynchronizedEventSubscriber.java:47)
at com.google.common.eventbus.EventBus.dispatch(EventBus.java:322)
at com.google.common.eventbus.EventBus.dispatchQueuedEvents(EventBus.java:304)
at com.google.common.eventbus.EventBus.post(EventBus.java:275)
at net.minecraftforge.fml.common.LoadController.distributeStateMessage(LoadController.java:118)
at net.minecraftforge.fml.common.Loader.preinitializeMods(Loader.java:556)
... 10 more
Caused by: java.lang.ClassNotFoundException: coco12345678910.TheCoconutMod.Blocks.BlockTest
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:191)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 39 more
Caused by: java.lang.NullPointerException
at net.minecraft.launchwrapper.LaunchClassLoader.findClass(LaunchClassLoader.java:182)
... 41 more


A detailed walkthrough of the error, its code path and all known details is as follows:
---------------------------------------------------------------------------------------

-- System Details --
Details:
Minecraft Version: 1.8.9
Operating System: Windows 8.1 (amd64) version 6.3
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 83477104 bytes (79 MB) / 269127680 bytes (256 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
FML: MCP 9.19 Powered by Forge 11.15.0.1708 7 mods loaded, 7 mods active
States: 'U' = Unloaded 'L' = Loaded 'C' = Constructed 'H' = Pre-initialized 'I' = Initialized 'J' = Post-initialized 'A' = Available 'D' = Disabled 'E' = Errored
UCH	mcp{9.18} [Minecraft Coder Pack] (minecraft.jar) 
UCH	FML{8.0.99.99} [Forge Mod Loader] (forge-1.8.9-11.15.0.1708.jar) 
UCH	Forge{11.15.0.1708} [Minecraft Forge] (forge-1.8.9-11.15.0.1708.jar) 
UCH	JEI{2.19.0.93} [Just Enough Items] (jei_1.8.9-2.19.0.93.jar) 
UCH	JEIAddons{0.9.0.32} [Just Enough Items Addons] (JEIAddons_1.8.9-0.9.0.32.jar) 
UCH	journeymap{5.1.3} [JourneyMap] (journeymap-1.8.8-5.1.3-unlimited.jar) 
UCE	tcm{1.0} [The Coconut Mod] (TheCoconutModv1.03(1.8.9).jar) 
Loaded coremods (and transformers): 
GL info: ' Vendor: 'Intel' Version: '4.3.0 - Build 10.18.10.3947' Renderer: 'Intel(R) HD Graphics 5500'

coco12345678910.TheCoconutMod.Blocks.BlockTest.java:

package coco12345678910.TheCoconutMod.Blocks;

import net.minecraft.block.Block;
import net.minecraft.block.material.Material;

public class BlockTest extends Block{

public BlockTest(Material materialIn) {
	super(materialIn);
}

}

coco12345678910.TheCoconutMod.TheCoconutModBlocks.java:

package coco12345678910.TheCoconutMod.init;

import coco12345678910.TheCoconutMod.Reference;
import coco12345678910.TheCoconutMod.TheCoconutMod;
import coco12345678910.TheCoconutMod.Blocks.BlockTest;
import net.minecraft.block.Block;
import net.minecraft.block.material.Material;
import net.minecraft.client.Minecraft;
import net.minecraft.client.resources.model.ModelResourceLocation;
import net.minecraft.item.Item;
import net.minecraftforge.fml.common.registry.GameRegistry;

public class TheCoconutModBlocks {

public static Block coconut_block;
public static Block coconut_ore;

public static void init(){

	coconut_block = new BlockTest(Material.wood).setUnlocalizedName("coconut_block").setCreativeTab(TheCoconutMod.tabCoconut);
	coconut_ore = new BlockTest(Material.iron).setUnlocalizedName("coconut_ore").setCreativeTab(TheCoconutMod.tabCoconut);
}

public static void register(){

	GameRegistry.registerBlock(coconut_block, coconut_block.getUnlocalizedName().substring(5));
	GameRegistry.registerBlock(coconut_ore, coconut_ore.getUnlocalizedName().substring(5));
}

public static void registerRenders(){

	registerRender(coconut_block);
	registerRender(coconut_ore);
}

public static void registerRender(Block block){

	Item item = Item.getItemFromBlock(block);
	Minecraft.getMinecraft().getRenderItem().getItemModelMesher().register(item, 0, new ModelResourceLocation(Reference.MOD_ID + ":" +item.getUnlocalizedName().substring(5), "inventory"));
}
}

How did you compile the mod?

It may not be the source of your problem, but build 1708 is neither recommended nor most recent. To get the best help with 1.8.9, you should probably update to the most recent build. If you look at all the bug fixes in the changelog, you'd understand why those in-the-know wouldn't want to sort errors in an old build.