ПОМОГИТЕ!!!! при запуске minecraft высвечивается вот это

Minecraft has crashed!
----------------------

Minecraft has stopped running because it encountered a problem; Unexpected error
We were unable to save this report to a file.

--- BEGIN ERROR REPORT 9e426084 --------
Generated 25.11.12 14:31

- Minecraft Version: 1.4.2
- Operating System: Windows 7 (x86) version 6.1
- Java Version: 1.7.0_09, Oracle Corporation
- Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
- Memory: 479387864 bytes (457 MB) / 519110656 bytes (495 MB) up to 1037959168 bytes (989 MB)
- JVM Flags: 2 total; -Xms512m -Xmx1024m
- AABB Pool Size: 0 (0 bytes; 0 MB) allocated, 0 (0 bytes; 0 MB) used
- LWJGL: 2.4.2
- OpenGL: Intel(R) HD Graphics 3000 GL version 3.1.0 - Build 8.15.10.2696, Intel
- Is Modded: Probably not
- Type: Client
- Texture Pack: Default
- Profiler Position: N/A (disabled)
- Vec3 Pool Size: ~ERROR~ NullPointerException: null

java.lang.RuntimeException: Failed to check session lock, aborting
at agt.h(SourceFile:49)
at agt.(SourceFile:35)
at agp.(SourceFile:16)
at agq.a(SourceFile:78)
at net.minecraft.client.Minecraft.a(SourceFile:1310)
at aru.a(SourceFile:204)
at asw.a(SourceFile:64)
at aru.a(SourceFile:305)
at asw.d(SourceFile:112)
at asw.m(SourceFile:100)
at net.minecraft.client.Minecraft.l(SourceFile:1077)
at net.minecraft.client.Minecraft.J(SourceFile:582)
at net.minecraft.client.Minecraft.run(SourceFile:534)
at java.lang.Thread.run(Unknown Source)
--- END ERROR REPORT c27690d7 ----------