Forge9.10.0.828 crashing minecraft on first startup when loading a world

[Codprimus]

I have followed 5 different tutorials and tried everything, but whenever i try to load a world with forge it says "shutting down internal server" and crashes. Can anybody help 

 

---- Minecraft Crash Report ----

// On the bright side, I bought you a teddy bear!

 

Time: 12/08/13 10:10

Description: Unexpected error

 

java.lang.ClassCastException: net.minecraft.client.entity.EntityClientPlayerMP cannot be cast to cpw.mods.fml.common.network.Player

at cpw.mods.fml.common.network.NetworkRegistry.handleCustomPacket(NetworkRegistry.java:245)

at cpw.mods.fml.common.network.FMLNetworkHandler.handlePacket250Packet(FMLNetworkHandler.java:84)

at net.minecraft.client.multiplayer.NetClientHandler.func_72501_a(NetClientHandler.java:1647)

at net.minecraft.network.packet.Packet250CustomPayload.func_73279_a(SourceFile:61)

at net.minecraft.network.MemoryConnection.func_74428_b(MemoryConnection.java:89)

at net.minecraft.client.Minecraft.func_71407_l(Minecraft.java:1953)

at net.minecraft.client.Minecraft.func_71411_J(Minecraft.java:898)

at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:826)

at net.minecraft.client.main.Main.main(SourceFile:101)

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 net.minecraft.launchwrapper.Launch.launch(Launch.java:57)

at net.minecraft.launchwrapper.Launch.main(Launch.java:18)

 

 

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

---------------------------------------------------------------------------------------

 

-- Head --

Stacktrace:

at cpw.mods.fml.common.network.NetworkRegistry.handleCustomPacket(NetworkRegistry.java:245)

at cpw.mods.fml.common.network.FMLNetworkHandler.handlePacket250Packet(FMLNetworkHandler.java:84)

at net.minecraft.client.multiplayer.NetClientHandler.func_72501_a(NetClientHandler.java:1647)

at net.minecraft.network.packet.Packet250CustomPayload.func_73279_a(SourceFile:61)

at net.minecraft.network.MemoryConnection.func_74428_b(MemoryConnection.java:89)

 

-- Affected level --

Details:

Level name: MpServer

All players: 1 total; [EntityClientPlayerMP['beneto12'/140, l='MpServer', x=8.50, y=66.62, z=8.50]]

Chunk stats: MultiplayerChunkCache: 0

Level seed: 0

Level generator: ID 01 - flat, ver 0. Features enabled: false

Level generator options:

Level spawn location: World: (8,64,, Chunk: (at 8,4,8 in 0,0; contains blocks 0,0,0 to 15,255,15), Region: (0,0; contains chunks 0,0 to 31,31, blocks 0,0,0 to 511,255,511)

Level time: 0 game time, 0 day time

Level dimension: 0

Level storage version: 0x00000 - Unknown?

Level weather: Rain time: 0 (now: false), thunder time: 0 (now: false)

Level game mode: Game mode: creative (ID 1). Hardcore: false. Cheats: false

Forced entities: 1 total; [EntityClientPlayerMP['beneto12'/140, l='MpServer', x=8.50, y=66.62, z=8.50]]

Retry entities: 0 total; []

Server brand: fml,forge

Server type: Integrated singleplayer server

Stacktrace:

at net.minecraft.client.multiplayer.WorldClient.func_72914_a(WorldClient.java:440)

at net.minecraft.client.Minecraft.func_71396_d(Minecraft.java:2298)

at net.minecraft.client.Minecraft.func_99999_d(Minecraft.java:851)

at net.minecraft.client.main.Main.main(SourceFile:101)

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 net.minecraft.launchwrapper.Launch.launch(Launch.java:57)

at net.minecraft.launchwrapper.Launch.main(Launch.java:18)

 

-- System Details --

Details:

Minecraft Version: 1.6.2

Operating System: Windows 8 (x86) version 6.2

Java Version: 1.7.0_25, Oracle Corporation

Java VM Version: Java HotSpot Client VM (mixed mode, sharing), Oracle Corporation

Memory: 187421312 bytes (178 MB) / 356843520 bytes (340 MB) up to 518979584 bytes (494 MB)

JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M

AABB Pool Size: 4625 (259000 bytes; 0 MB) allocated, 4625 (259000 bytes; 0 MB) used

Suspicious classes: FML and Forge are installed

IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0

FML: MCP v8.04 FML v6.2.43.828 Minecraft Forge 9.10.0.828 3 mods loaded, 3 mods active

mcp{8.04} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available

FML{6.2.43.828} [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available

Forge{9.10.0.828} [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available

Launched Version: 1.6.2-Forge9.10.0.828

LWJGL: 2.9.0

OpenGL: AMD Radeon HD 7340G GL version 4.2.11764 Compatibility Profile Context, ATI Technologies Inc.

Is Modded: Definitely; Client brand changed to 'fml,forge'

Type: Client (map_client.txt)

Resource Pack: Default

Current Language: Pirate Speak (PIRATE)

Profiler Position: N/A (disabled)

Vec3 Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used

[LexManos]

How did you install Forge?

It seems that the marker class file is not accessible to forge.

[Codprimus]

I figured it out, turns out i had some older mod files in my .minecraft folder after i reset the folder everything was fine