No carga mundo ni genera terreno y termina diciendo que no responde.
El error que sale es el siguiente:

---- Minecraft Crash Report ----
// You should try our sister game, Minceraft!


Time: 22/06/15 16:53
Description: Updating screen events


java.lang.IllegalStateException: failed to create a child event loop
at io.netty.util.concurrent.MultithreadEventExecutorG roup.<init>(MultithreadEventExecutorGroup.java:68)
at io.netty.channel.MultithreadEventLoopGroup.<init>( MultithreadEventLoopGroup.java:49)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioE ventLoopGroup.java:61)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioE ventLoopGroup.java:52)
at ll$1.a(SourceFile:44)
at ll$1.b(SourceFile:41)
at no.c(SourceFile:10)
at ll.a(SourceFile:121)
at ave.a(SourceFile:1941)
at axv.i(SourceFile:172)
at axv.a(SourceFile:135)
at axu.a(SourceFile:350)
at axu.k(SourceFile:413)
at axv.k(SourceFile:81)
at axu.p(SourceFile:390)
at ave.s(SourceFile:1497)
at ave.av(SourceFile:888)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124 )
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(Nio EventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventL oop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(Ni oEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorG roup.<init>(MultithreadEventExecutorGroup.java:64)
... 18 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java: 101)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java: 68)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:170)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorP roviderImpl.java:50)
at java.nio.channels.Pipe.open(Pipe.java:155)
at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelec torImpl.java:127)
at sun.nio.ch.WindowsSelectorProvider.openSelector(Wi ndowsSelectorProvider.java:44)
at io.netty.channel.nio.NioEventLoop.openSelector(Nio EventLoop.java:126)
... 21 more
Caused by: java.net.ConnectException: Connection timed out: connect
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Net.java:457)
at sun.nio.ch.Net.connect(Net.java:449)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannel Impl.java:647)
at java.nio.channels.SocketChannel.open(SocketChannel .java:189)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector. run(PipeImpl.java:130)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java: 83)
... 29 more




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


-- Head --
Stacktrace:
at io.netty.util.concurrent.MultithreadEventExecutorG roup.<init>(MultithreadEventExecutorGroup.java:68)
at io.netty.channel.MultithreadEventLoopGroup.<init>( MultithreadEventLoopGroup.java:49)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioE ventLoopGroup.java:61)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioE ventLoopGroup.java:52)
at ll$1.a(SourceFile:44)
at ll$1.b(SourceFile:41)
at no.c(SourceFile:10)
at ll.a(SourceFile:121)
at ave.a(SourceFile:1941)
at axv.i(SourceFile:172)
at axv.a(SourceFile:135)
at axu.a(SourceFile:350)
at axu.k(SourceFile:413)
at axv.k(SourceFile:81)
at axu.p(SourceFile:390)


-- Affected screen --
Details:
Screen name: aya
Stacktrace:
at ave.s(SourceFile:1497)
at ave.av(SourceFile:888)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124 )


-- System Details --
Details:
Minecraft Version: 1.8.7
Operating System: Windows 7 (amd64) version 6.1
CPU: 4x Intel(R) Core(TM) i5-2500 CPU @ 3.30GHz
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 86414760 bytes (82 MB) / 322105344 bytes (307 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerform ance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 1.8.7
LWJGL: 2.9.4
OpenGL: GeForce 405/PCIe/SSE2 GL version 3.3.0, NVIDIA Corporation
GL Caps: Using GL 1.3 multitexturing.
Using GL 1.3 texture combiners.
Using framebuffer objects because OpenGL 3.0 is supported and separate blending is supported.
Shaders are available because OpenGL 2.1 is supported.
VBOs are available because OpenGL 1.5 is supported.


Using VBOs: No
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs:
Current Language: Español (España)
Profiler Position: N/A (disabled)