heres my crash report and i have the same problem but no mods
---- Minecraft Crash Report ----
// Don't be sad. I'll do better next time, I promise!

Time: 11/11/13 5:58 PM
Description: Ticking screen

java.lang.NullPointerException: Ticking screen
at biv.a(SourceFile:589)
at hg.a(SourceFile:32)
at hg.a(SourceFile:13)
at ef.a(SourceFile:164)
at bbe.c(SourceFile:76)
at azd.o(SourceFile:1318)
at azd.ad(SourceFile:753)
at azd.e(SourceFile:704)
at net.minecraft.client.main.Main.main(SourceFile:103)


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

-- Head --
Stacktrace:
at biv.a(SourceFile:589)
at hg.a(SourceFile:32)
at hg.a(SourceFile:13)
at ef.a(SourceFile:164)
at bbe.c(SourceFile:76)

-- Affected screen --
Details:
Screen name: bbe
Stacktrace:
at azd.o(SourceFile:1318)
at azd.ad(SourceFile:753)
at azd.e(SourceFile:704)
at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
Minecraft Version: 1.7.2
Operating System: Mac OS X (x86_64) version 10.8.5
Java Version: 1.6.0_65, Apple Inc.
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Apple Inc.
Memory: 63546904 bytes (60 MB) / 97685504 bytes (93 MB) up to 1065025536 bytes (1015 MB)
JVM Flags: 1 total; -Xmx1G
AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
IntCache: cache: 0, tcache: 0, allocated: 0, tallocated: 0
Launched Version: 1.7.2
LWJGL: 2.9.1
OpenGL: NVIDIA GeForce GT 330M OpenGL Engine GL version 2.1 NVIDIA-8.16.74 310.40.00.10f02, NVIDIA Corporation
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs: []
Current Language: English (US)
Profiler Position: N/A (disabled)
Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
Anisotropic Filtering: Off (1)

Well i'm no expert but i can clearly see that you have mods installed. Since Hypixels server doesn't have any mods that's probably why it crashes. That's my guess.

Just recently been having problems with crashes. Here's my error report... can someone tell me why this started to happen? Thanks...


--- BEGIN ERROR REPORT 158dbab7 --------
Full report at:
C:\Users\User\AppData\Roaming\.minecraft\crash-reports\crash-2013-08-16_02.49.37-server.txt
Please show that file to Mojang, NOT just this screen!

Generated 8/16/13 2:49 AM

-- System Details --
Details:
Minecraft Version: 1.5.2
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.7.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 182852040 bytes (174 MB) / 519110656 bytes (495 MB) up to 1037959168 bytes (989 MB)
JVM Flags: 2 total; -Xms512m -Xmx1024m
AABB Pool Size: 5805 (325080 bytes; 0 MB) allocated, 5604 (313824 bytes; 0 MB) used
Suspicious classes: FML and Forge are installed
IntCache: cache: 0, tcache: 0, allocated: 3, tallocated: 71
FML: MCP v7.51 FML v5.2.23.737 Minecraft Forge 7.8.1.737 86 mods loaded, 86 mods active
mcp{7.51} [Minecraft Coder Pack] (minecraft.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
FML{5.2.23.737} [Forge Mod Loader] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Forge{7.8.1.737} [Minecraft Forge] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
CodeChickenCore{0.8.7.1} [CodeChicken Core] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
NotEnoughItems{1.5.2.28} [Not Enough Items] (coremods) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
GuiAPI{0.15.6} [GuiAPI] (GuiAPI-0.15.6-1.5.2.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
mod_ReiMinimap{v3.3_05 [1.5.2]} [mod_ReiMinimap] ([1.5.2]ReiMinimap_v3.3_05.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
cfm{2.8.5} [MrCrayfish's Furniture Mod] ([Forge]FurnitureMod2.8.3(FULL).zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Backpack{1.8.9} [Backpack] (backpack-1.8.9-1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
BiblioCraft{1.3.1} [BiblioCraft] (BiblioCraft[v1.3.1].zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
CustomSpawner{2.2.1} [DrZhark's CustomSpawner] (CustomMobSpawner 2.2.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
MoCreatures{5.2.2} [DrZhark's Mo'Creatures Mod] (DrZharks MoCreatures Mod v5.2.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
SlimevoidLib{2.0.1.1} [Slimevoid Library] (SlimevoidLib-Universal-v2.0.1.1.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
DynamicElevators{2.0.0.4} [Dynamic Elevators] (DynamicElevators-Universal-v2.0.0.4.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Millenaire{4.9.4} [Millénaire] (millenaire4.9.4.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBlackberry{1.0} [Pam's HarvestCraft Blackberry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBlueberry{1.0} [Pam's HarvestCraft Blueberry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCactusfruit{1.0} [Pam's HarvestCraft Cactusfruit] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCranberry{1.0} [Pam's HarvestCraft Cranberry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCGrape{1.0} [Pam's HarvestCraft Grape] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCKiwi{1.0} [Pam's HarvestCraft Kiwi] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCRaspberry{1.0} [Pam's HarvestCraft Raspberry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCSpiceleaf{1.0} [Pam's HarvestCraft Spiceleaf] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCStrawberry{1.0} [Pam's HarvestCraft Strawberry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCSunflower{1.0} [Pam's HarvestCraft Sunflower] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCWhitemushroom{1.0} [Pam's HarvestCraft Whitemushroom] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCAsparagus{1.0} [Pam's HarvestCraft Asparagus] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBean{1.0} [Pam's HarvestCraft Bean] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBeet{1.0} [Pam's HarvestCraft Beet] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBroccoli{1.0} [Pam's HarvestCraft Broccoli] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCelery{1.0} [Pam's HarvestCraft Celery] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCGarlic{1.0} [Pam's HarvestCraft Garlic] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCGinger{1.0} [Pam's HarvestCraft Ginger] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCLettuce{1.0} [Pam's HarvestCraft Lettuce] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCOnion{1.0} [Pam's HarvestCraft Onion] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPeanut{1.0} [Pam's HarvestCraft Peanut] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPineapple{1.0} [Pam's HarvestCraft Pineapple] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCRadish{1.0} [Pam's HarvestCraft Radish] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCRice{1.0} [Pam's HarvestCraft Rice] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCRotten{1.0} [Pam's HarvestCraft Rotten] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCSweetpotato{1.0} [Pam's HarvestCraft Sweetpotato] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCTea{1.0} [Pam's HarvestCraft Tea] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCTurnip{1.0} [Pam's HarvestCraft Turnip] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBellpepper{1.0} [Pam's HarvestCraft Bellpepper] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCantaloupe{1.0} [Pam's HarvestCraft Cantaloupe] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCChilipepper{1.0} [Pam's HarvestCraft Chilipepper] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCoffee{1.0} [Pam's HarvestCraft Coffee] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCorn{1.0} [Pam's HarvestCraft Corn] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCucumber{1.0} [Pam's HarvestCraft Cucumber] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCEggplant{1.0} [Pam's HarvestCraft Eggplant] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCMustard{1.0} [Pam's HarvestCraft Mustard] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPeas{1.0} [Pam's HarvestCraft Peas] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCTomato{1.0} [Pam's HarvestCraft Tomato] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCZucchini{1.0} [Pam's HarvestCraft Zucchini] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCandle{1.0} [Pam's HarvestCraft Candle] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCotton{1.0} [Pam's HarvestCraft Cotton] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCSalt{1.0} [Pam's HarvestCraft - Salt] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCSink{1.0} [Pam's HarvestCraft Sink] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCVanillastorage{1.0} [Pam's HarvestCraft - Vanilla Storage Blocks] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHarvestCraft{1.0} [Pam's HarvestCraft Base] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCApple{1.0} [Pam's HarvestCraft Apple] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCAvocado{1.0} [Pam's HarvestCraft Avocado] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCBanana{1.0} [Pam's HarvestCraft Banana] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCherry{1.0} [Pam's HarvestCraft Cherry] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCinnamon{1.0} [Pam's HarvestCraft Cinnamon] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCCoconut{1.0} [Pam's HarvestCraft Coconut] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCDragonfruit{1.0} [Pam's HarvestCraft Dragonfruit] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCLemon{1.0} [Pam's HarvestCraft Lemon] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCLime{1.0} [Pam's HarvestCraft Lime] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCMango{1.0} [Pam's HarvestCraft Mango] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCNutmeg{1.0} [Pam's HarvestCraft Nutmeg] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCOlive{1.0} [Pam's HarvestCraft Olive] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCOrange{1.0} [Pam's HarvestCraft Orange] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPapaya{1.0} [Pam's HarvestCraft Papaya] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPeach{1.0} [Pam's HarvestCraft Peach] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPear{1.0} [Pam's HarvestCraft Pear] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPeppercorn{1.0} [Pam's HarvestCraft Peppercorn] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPlum{1.0} [Pam's HarvestCraft Plum] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCPomegranate{1.0} [Pam's HarvestCraft Pomegranate] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCStarfruit{1.0} [Pam's HarvestCraft Starfruit] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCVanillabean{1.0} [Pam's HarvestCraft Vanillabean] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
PamHCWalnut{1.0} [Pam's HarvestCraft Walnut] (Pams_HarvestCraft_1.01_-_MC_1.5.2.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Schematica{1.5.2.38} [Schematica] (Schematica.jar) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
secretroomsmod{4.6.0} [SecretRoomsMod] (SecretRoomsMod-universal-4.6.0.283.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
mod_SmartMoving{13.9} [Smart Moving] (Smart Moving Universal for ModLoader or Minecraft Forge or MCPC+.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
mod_SmartRender{1.1} [Smart Render] (Smart Moving Universal for ModLoader or Minecraft Forge or MCPC+.zip) Unloaded->Constructed->Pre-initialized->Initialized->Post-initialized->Available->Available->Available->Available
Profiler Position: N/A (disabled)
Vec3 Pool Size: 5553 (310968 bytes; 0 MB) allocated, 4680 (262080 bytes; 0 MB) used
Player Count: 1 / 8; [EntityPlayerMP['Rayne'/520, l='Arjentos', x=219.14, y=112.00, z=103.13]]
Type: Integrated Server (map_client.txt)
Is Modded: Definitely; Client brand changed to 'fml,forge'

java.lang.NoClassDefFoundError: net/minecraft/world/CallableLvl1
at net.minecraft.world.World.func_72821_m(World.java:861)
at net.minecraft.world.World.func_72898_h(World.java:787)
at net.minecraft.world.World.func_72851_f(World.java:740)
at net.minecraft.world.World.func_72832_d(World.java:572)
at com.mrcrayfish.furniture.BlockLampOn.func_71903_a(BlockLampOn.java:65)
at net.minecraft.item.ItemInWorldManager.func_73078_a(ItemInWorldManager.java:412)
at net.minecraft.network.NetServerHandler.func_72472_a(NetServerHandler.java:553)
at net.smart.moving.playerapi.NetServerHandler.func_72472_a(NetServerHandler.java:42)
at net.minecraft.network.packet.Packet15Place.func_73279_a(SourceFile:58)
at net.minecraft.network.MemoryConnection.func_74428_b(MemoryConnection.java:89)
at net.minecraft.network.NetServerHandler.func_72570_d(NetServerHandler.java:134)
at net.minecraft.network.NetworkListenThread.func_71747_b(NetworkListenThread.java:53)
at net.minecraft.server.integrated.IntegratedServerListenThread.func_71747_b(IntegratedServerListenThread.java:109)
at net.minecraft.server.MinecraftServer.func_71190_q(MinecraftServer.java:677)
at net.minecraft.server.MinecraftServer.func_71217_p(MinecraftServer.java:573)
at net.minecraft.server.integrated.IntegratedServer.func_71217_p(IntegratedServer.java:127)
at net.minecraft.server.MinecraftServer.run(MinecraftServer.java:470)
at net.minecraft.server.ThreadMinecraftServer.run(SourceFile:573)
--- END ERROR REPORT 7d128950 ----------

If you just got minecraft ur computer isn't used to all the things it runs on it. This happens for at least 2 weeks then it dosnt crash as much.
It may crash if theres too much lag or something
Hope this helps

Can you post the crash report? Hard to help without it.

Do you have mods installed? Also go to %appdata% and delete the .minecraft folder and reinstall the game and make sure you have the latest java and video card drivers.

When your in the Minecraft Launcher Go to Options
ForceUpdate.

If that does not work try to allocate more Ram To java.
Google That