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Game Crashing when trying to load single player worlds and can't connect to any serves (java.land.NullPointerException)

---- Minecraft Crash Report ----
// I'm sorry, Dave.

Time: 12/20/16 2:24 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 mh$1.a(SourceFile:61)
at mh$1.b(SourceFile:58)
at op.c(SourceFile:10)
at mh.a(SourceFile:152)
at bes.a(SourceFile:2162)
at bkb.e(SourceFile:229)
at bkb.a(SourceFile:182)
at bkb.a(SourceFile:154)
at bfy.b(SourceFile:41)
at bka.a(SourceFile:117)
at bho.k(SourceFile:404)
at bka.k(SourceFile:49)
at bho.p(SourceFile:381)
at bes.t(SourceFile:1586)
at bes.av(SourceFile:970)
at bes.a(SourceFile:398)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
... 20 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:101)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:68)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:170)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50)
at java.nio.channels.Pipe.open(Pipe.java:155)
at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:127)
at sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44)
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126)
... 23 more
Caused by: java.net.SocketException: Permission denied: connect
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Net.java:457)
at sun.nio.ch.Net.connect(Net.java:449)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:647)
at java.nio.channels.SocketChannel.open(SocketChannel.java:189)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:130)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:83)
... 31 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 bes.a(SourceFile:2162)
at bkb.e(SourceFile:229)
at bkb.a(SourceFile:182)
at bkb.a(SourceFile:154)
at bfy.b(SourceFile:41)
at bka.a(SourceFile:117)
at bho.k(SourceFile:404)
at bka.k(SourceFile:49)
at bho.p(SourceFile:381)

-- Affected screen --
Details:
Screen name: bhm
Stacktrace:
at bes.t(SourceFile:1586)
at bes.av(SourceFile:970)
at bes.a(SourceFile:398)
at net.minecraft.client.main.Main.main(SourceFile:124)

-- System Details --
Details:
Minecraft Version: 1.11.1
Operating System: Windows 10 (amd64) version 10.0
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 91499056 bytes (87 MB) / 286228480 bytes (272 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: 1.11.1
LWJGL: 2.9.4
OpenGL: GeForce GTX 960/PCIe/SSE2 GL version 4.5.0 NVIDIA 376.33, 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: Yes
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)
CPU: 8x AMD FX(tm)-8320 Eight-Core Processor

Caused by: java.net.SocketException: Permission denied: connect

This is a firewall type issue. Even single player minecraft needs to access a network socket for the client/server communications.

The particular java being used must be allowed access....

So, how do I fix it?

I fixed it by putting this command into cmd

setx _JAVA_OPTIONS -Djava.net.preferIPv4Stack=true

If you are having the same issue, use this video