Hopper: java.lang.RuntimeException: Failed to check session lock, aborting

This is an automatically generated report based from the following crash: http://hopper.minecraft.net/crashes/minecraft/MCX-465261/

Crash:

java.lang.RuntimeException: Failed to check session lock, aborting
	at axc.h(SourceFile:48)
	at axc.<init>(SourceFile:34)
	at awy.<init>(SourceFile:16)
	at awz.a(SourceFile:71)
	at azd.a(SourceFile:1578)
	at bce.e(SourceFile:162)
	at bcf.a(SourceFile:214)
	at bay.a(SourceFile:186)
	at bce.a(SourceFile:187)

The following is the first clean report made public about this crash:

---- Minecraft Crash Report ----
// Don't be sad. I'll do better next time, I promise!

Time: 25.10.13 15:57
Description: Rendering screen

java.lang.RuntimeException: Failed to check session lock, aborting
	at axc.h(SourceFile:48)
	at axc.<init>(SourceFile:34)
	at awy.<init>(SourceFile:16)
	at awz.a(SourceFile:71)
	at azd.a(SourceFile:1578)
	at bce.e(SourceFile:162)
	at bcf.a(SourceFile:214)
	at bay.a(SourceFile:186)
	at bce.a(SourceFile:187)
	at bll.b(SourceFile:851)
	at azd.ad(SourceFile:780)
	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 axc.h(SourceFile:48)
	at axc.<init>(SourceFile:34)
	at awy.<init>(SourceFile:16)
	at awz.a(SourceFile:71)
	at azd.a(SourceFile:1578)
	at bce.e(SourceFile:162)
	at bcf.a(SourceFile:214)
	at bay.a(SourceFile:186)
	at bce.a(SourceFile:187)

-- Screen render details --
Details:
	Screen name: btj
	Mouse location: Scaled: (188, 131). Absolute: (564, 352)
	Screen size: Scaled: (456, 249). Absolute: (1366, 745). Scale factor of 3
Stacktrace:
	at bll.b(SourceFile:851)
	at azd.ad(SourceFile:780)
	at azd.e(SourceFile:704)
	at net.minecraft.client.main.Main.main(SourceFile:103)

-- System Details --
Details:
	Minecraft Version: 1.7.2
	Operating System: Windows 8 (x86) version 6.2
	Java Version: 1.7.0_21, Oracle Corporation
	Java VM Version: Java HotSpot(TM) Client VM (mixed mode, sharing), Oracle Corporation
	Memory: 178753704 bytes (170 MB) / 305561600 bytes (291 MB) up to 518979584 bytes (494 MB)
	JVM Flags: 2 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M
	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: 2.9.0
	OpenGL: GeForce GT 630M/PCIe/SSE2 GL version 4.3.0, NVIDIA Corporation
	Is Modded: Probably not. Jar signature remains and client brand is untouched.
	Type: Client (map_client.txt)
	Resource Packs: [Misa.zip]
	Current Language: Deutsch (Deutschland)
	Profiler Position: N/A (disabled)
	Vec3 Pool Size: ~~ERROR~~ NullPointerException: null
	Anisotropic Filtering: Off (1)

You can see this full report at http://hopper.minecraft.net/crashes/minecraft/MCX-465261/21353061/