Put the summary of the bug you're having here

---- Minecraft Crash Report ----
// Surprise! Haha. Well, this is awkward.

Time: 16年11月26日 下午5:44
Description: Updating screen events

java.lang.IllegalStateException: failed to create a child event loop
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:68)
at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:49)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:61)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:52)
at mh$1.a(SourceFile:61)
at mh$1.b(SourceFile:58)
at op.c(SourceFile:10)
at mh.a(SourceFile:152)
at beq.a(SourceFile:2159)
at bjz.e(SourceFile:229)
at bjz.a(SourceFile:182)
at bjz.a(SourceFile:154)
at bfw.b(SourceFile:41)
at bjy.a(SourceFile:117)
at bhm.k(SourceFile:404)
at bjy.k(SourceFile:49)
at bhm.p(SourceFile:381)
at beq.t(SourceFile:1583)
at beq.av(SourceFile:967)
at beq.a(SourceFile:395)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
... 20 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(Unknown Source)
at sun.nio.ch.PipeImpl$Initializer.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(Unknown Source)
at sun.nio.ch.SelectorProviderImpl.openPipe(Unknown Source)
at java.nio.channels.Pipe.open(Unknown Source)
at sun.nio.ch.WindowsSelectorImpl.<init>(Unknown Source)
at sun.nio.ch.WindowsSelectorProvider.openSelector(Unknown Source)
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126)
... 23 more
Caused by: java.net.ConnectException: Connection timed out: connect
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Unknown Source)
at sun.nio.ch.Net.connect(Unknown Source)
at sun.nio.ch.SocketChannelImpl.connect(Unknown Source)
at java.nio.channels.SocketChannel.open(Unknown Source)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(Unknown Source)
... 32 more

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

– Head –
Thread: Client thread
Stacktrace:
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:68)
at io.netty.channel.MultithreadEventLoopGroup.<init>(MultithreadEventLoopGroup.java:49)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:61)
at io.netty.channel.nio.NioEventLoopGroup.<init>(NioEventLoopGroup.java:52)
at mh$1.a(SourceFile:61)
at mh$1.b(SourceFile:58)
at op.c(SourceFile:10)
at mh.a(SourceFile:152)
at beq.a(SourceFile:2159)
at bjz.e(SourceFile:229)
at bjz.a(SourceFile:182)
at bjz.a(SourceFile:154)
at bfw.b(SourceFile:41)
at bjy.a(SourceFile:117)
at bhm.k(SourceFile:404)
at bjy.k(SourceFile:49)
at bhm.p(SourceFile:381)

– Affected screen –
Details:
Screen name: bhk
Stacktrace:
at beq.t(SourceFile:1583)
at beq.av(SourceFile:967)
at beq.a(SourceFile:395)
at net.minecraft.client.main.Main.main(SourceFile:124)

– System Details –
Details:
Minecraft Version: 1.11
Operating System: Windows 7 (x86) version 6.1
Java Version: 1.8.0_101, Oracle Corporation
Java VM Version: Java HotSpot(TM) Client VM (mixed mode), Oracle Corporation
Memory: 145862992 bytes (139 MB) / 319905792 bytes (305 MB) up to 523501568 bytes (499 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx512M -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 12, tallocated: 94
Launched Version: 1.11
LWJGL: 2.9.4
OpenGL: Intel(R) HD Graphics 2000 GL version 3.1.0 - Build 9.17.10.3347, Intel
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: Yes
Is Modded: Probably not. Jar signature remains and client brand is untouched.
Type: Client (map_client.txt)
Resource Packs:
Current Language: 繁體中文 (台灣)
Profiler Position: N/A (disabled)
CPU: 4x Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
3. ...