[1.7.10]: Using missing texture, unable to load

Hi, I have problem with loading texture for my custom block. Console keep saying : Using missing texture, unable to load... and I cant solve it. I think i have textures in right folder but they still dont work. What is strange is that my language file works.

Here is BlockrockBrick.java:

package com.alven4;

import net.minecraft.block.Block;

import net.minecraft.block.material.Material;

import net.minecraft.creativetab.*;

public class BlockrockBrick extends Block {

public BlockrockBrick(Material rock) {

super(Material.rock);

setBlockName("rockBrick");

setBlockTextureName(MOD.MODID+":"+"rockBrick");

setCreativeTab(CreativeTabs.tabBlock);

// TODO Auto-generated constructor stub

}}

My folder system looks:

src/main/

            java

                  com/alven4

                              MOD.java

                              BlockrockBrick.java

            resources/assets/MOD

                                          lang/en_US.lang

                                          textures/blocks/rockBrick.png

And here my main code:

package com.alven4;

import java.io.File;

import net.minecraft.block.Block;

import net.minecraft.init.Blocks;

import net.minecraft.init.Items;

import net.minecraft.item.ItemStack;

import cpw.mods.fml.common.Mod;

import cpw.mods.fml.common.Mod.EventHandler;

import cpw.mods.fml.common.event.FMLInitializationEvent;

import cpw.mods.fml.common.event.FMLPreInitializationEvent;

import cpw.mods.fml.common.registry.GameRegistry;

@Mod(modid = MOD.MODID, version = MOD.VERSION)

public class MOD

{

    public static final String MODID = "MOD";

    public static final String VERSION = "4.0";

    public static Block rockBrick;

@EventHandler

    public void preinit(FMLPreInitializationEvent event)

    {

    rockBrick  = new BlockrockBrick(null);

    GameRegistry.registerBlock(rockBrick, "rockBrick");

    ItemStack starStack = new ItemStack(Items.nether_star);

GameRegistry.addRecipe(new ItemStack(Blocks.command_block,1), new Object[]{"121","212","121",

'1',starStack,'2',new ItemStack(Blocks.bedrock)});

GameRegistry.addShapelessRecipe(new ItemStack(Items.iron_ingot,1), new Object[]{

new ItemStack(Blocks.rail),new ItemStack(Blocks.rail),new ItemStack(Blocks.rail),new ItemStack(Blocks.rail)

});

GameRegistry.addSmelting(Blocks.diamond_block, new ItemStack(Blocks.lava), (float) 0.001);

GameRegistry.addRecipe(new ItemStack(Blocks.bedrock), new Object[]{

"LLL","LLL","LLL",'L',new ItemStack(Blocks.lava)

});

    }

    @EventHandler

    public void init(FMLInitializationEvent event)

    {

// some example code

        System.out.println("DIRT BLOCK >> "+Blocks.dirt.getUnlocalizedName());

    }

}