I opened my launcher,then i saw a Play offline button,i thought it was my internet,so i play offline.Then when i want to play single player,this happened.
---- Minecraft Crash Report ----
// Ouch. That hurt

Time: 01/08/15 11:33
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$1.b(SourceFile:41)
at no.c(SourceFile:10)
at ll.a(SourceFile:121)
at ave.a(SourceFile:1941)
at axv.i(SourceFile:172)
at axv.a(SourceFile:135)
at axu.a(SourceFile:350)
at axu.k(SourceFile:413)
at axv.k(SourceFile:81)
at axu.p(SourceFile:390)
at ave.s(SourceFile:1497)
at ave.av(SourceFile:888)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
... 18 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:101)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:68)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:170)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50)
at java.nio.channels.Pipe.open(Pipe.java:155)
at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:127)
at sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44)
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126)
... 21 more
Caused by: java.net.SocketException: Unrecognized Windows Sockets error: 87: socket
at sun.nio.ch.Net.socket0(Native Method)
at sun.nio.ch.Net.serverSocket(Net.java:419)
at sun.nio.ch.ServerSocketChannelImpl.<init>(ServerSocketChannelImpl.java:88)
at sun.nio.ch.SelectorProviderImpl.openServerSocketChannel(SelectorProviderImpl.java:56)
at java.nio.channels.ServerSocketChannel.open(ServerSocketChannel.java:108)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:123)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:83)
... 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.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 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) i5-3450 CPU @ 3.10GHz
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 75783024 bytes (72 MB) / 237502464 bytes (226 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: 0, tallocated: 0
Launched Version: 1.8.7
LWJGL: 2.9.4
OpenGL: Intel(R) HD Graphics GL version 3.3.0 - Build 8.15.10.2598, 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: 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)
Also i tried to log out and log in to make it worked but it makes me cant log in.
Here is the problem
SocketException:Unrecognize Windows Sockets error: 87: create