Put the summary of the bug you're having here

Minecraft Crash Report ----
// Uh... Did I do that?

Time: 9/4/15 3:59 PM
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 ll$1.a(SourceFile:44)
at ll$1.b(SourceFile:41)
at no.c(SourceFile:10)
at ll.a(SourceFile:121)
at ave.a(SourceFile:1941)
at axb.a(SourceFile:210)
at axu.a(SourceFile:350)
at axb.a(SourceFile:350)
at axu.k(SourceFile:413)
at axu.p(SourceFile:390)
at ave.s(SourceFile:1497)
at ave.av(SourceFile:888)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
... 17 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:101)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:68)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:170)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50)
at java.nio.channels.Pipe.open(Pipe.java:155)
at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:127)
at sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44)
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126)
... 20 more
Caused by: java.net.SocketException: Unrecognized Windows Sockets error: 10107: socket
at sun.nio.ch.Net.socket0(Native Method)
at sun.nio.ch.Net.serverSocket(Net.java:419)
at sun.nio.ch.ServerSocketChannelImpl.<init>(ServerSocketChannelImpl.java:88)
at sun.nio.ch.SelectorProviderImpl.openServerSocketChannel(SelectorProviderImpl.java:56)
at java.nio.channels.ServerSocketChannel.open(ServerSocketChannel.java:108)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:123)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:83)
... 28 more

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

– Head –
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 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 axb.a(SourceFile:210)
at axu.a(SourceFile:350)
at axb.a(SourceFile:350)
at axu.k(SourceFile:413)
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: 1.8.4
Operating System: Windows 8.1 (amd64) version 6.3
CPU: 4x AMD A10-5745M APU with Radeon(tm) HD Graphics
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 118429464 bytes (112 MB) / 306245632 bytes (292 MB) up to 1060372480 bytes (1011 MB)
JVM Flags: 6 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xmx1G -XX:+UseConcMarkSweepGC -XX:+CMSIncrementalMode -XX:-UseAdaptiveSizePolicy -Xmn128M
IntCache: cache: 0, tcache: 0, allocated: 13, tallocated: 95
Launched Version: 1.8.4
LWJGL: 2.9.4
OpenGL: AMD Radeon(TM) HD 8610G GL version 4.3.12804 Compatibility Profile Context 13.352.1004.1016, ATI Technologies Inc.
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: English (US)
Profiler Position: N/A (disabled)3. ...