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Hello. For a month and so I have been encountering an error that I have been trying to resolve, but my methods never work. I have encountered a java.lang.IllegalStateException: failed to create a child event loop

In my guess, this error occurs when an Antivirus, Java, or any software is blocking the game. When I first had the error, it DID show what my game was going through Mojira Issue MC-34749, where it was blocked by an antivirus, so I uninstalled McAffe, but it Didn't Work! The only difference is that the crash screen doesn't encounter Mojira, and here is the latest crash screen I had when trying to run minecraft was this:

---- Minecraft Crash Report ----
// Don't do that.

Time: 8/23/15 5:29 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$1.b(SourceFile:41)
at no.c(SourceFile:10)
at ll.a(SourceFile:121)
at ave.a(SourceFile:1942)
at axb.a(SourceFile:210)
at axu.a(SourceFile:350)
at axb.a(SourceFile:350)
at axu.k(SourceFile:413)
at axu.p(SourceFile:390)
at ave.s(SourceFile:1498)
at ave.av(SourceFile:889)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)
Caused by: io.netty.channel.ChannelException: failed to open a new selector
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:128)
at io.netty.channel.nio.NioEventLoop.<init>(NioEventLoop.java:120)
at io.netty.channel.nio.NioEventLoopGroup.newChild(NioEventLoopGroup.java:87)
at io.netty.util.concurrent.MultithreadEventExecutorGroup.<init>(MultithreadEventExecutorGroup.java:64)
... 17 more
Caused by: java.io.IOException: Unable to establish loopback connection
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:101)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:68)
at java.security.AccessController.doPrivileged(Native Method)
at sun.nio.ch.PipeImpl.<init>(PipeImpl.java:170)
at sun.nio.ch.SelectorProviderImpl.openPipe(SelectorProviderImpl.java:50)
at java.nio.channels.Pipe.open(Pipe.java:155)
at sun.nio.ch.WindowsSelectorImpl.<init>(WindowsSelectorImpl.java:127)
at sun.nio.ch.WindowsSelectorProvider.openSelector(WindowsSelectorProvider.java:44)
at io.netty.channel.nio.NioEventLoop.openSelector(NioEventLoop.java:126)
... 20 more
Caused by: java.net.ConnectException: Connection timed out: connect
at sun.nio.ch.Net.connect0(Native Method)
at sun.nio.ch.Net.connect(Net.java:457)
at sun.nio.ch.Net.connect(Net.java:449)
at sun.nio.ch.SocketChannelImpl.connect(SocketChannelImpl.java:647)
at java.nio.channels.SocketChannel.open(SocketChannel.java:189)
at sun.nio.ch.PipeImpl$Initializer$LoopbackConnector.run(PipeImpl.java:130)
at sun.nio.ch.PipeImpl$Initializer.run(PipeImpl.java:83)
... 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:1942)
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:1498)
at ave.av(SourceFile:889)
at ave.a(SourceFile:325)
at net.minecraft.client.main.Main.main(SourceFile:124)

-- System Details --
Details:
Minecraft Version: 1.8.8
Operating System: Windows 7 (amd64) version 6.1
Java Version: 1.8.0_25, Oracle Corporation
Java VM Version: Java HotSpot(TM) 64-Bit Server VM (mixed mode), Oracle Corporation
Memory: 182480480 bytes (174 MB) / 329232384 bytes (313 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: 1, tcache: 1, allocated: 12, tallocated: 94
Launched Version: 1.8.8
LWJGL: 2.9.4
OpenGL: Intel(R) HD Graphics Family GL version 3.1.0 - Build 8.15.10.2372, 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)
CPU: 2x Intel(R) Pentium(R) CPU G620T @ 2.20GHz

I have tried many methods, but failed. Below lists the methods I tried to fix my MC in chronological order:

#Reinstalled Minecraft (2 times)

#Uninstalled McAffe and rebooted (I had to install it again)

#Updated Java to the latest version and reinstalled it (My launcher is not on java)

#Shut down my computer {MANY TIMES}

#And deleted .minecraft 2 times; The 2nd time I shut down my computer and then run minecraft.

------------------------------------------------------------------------------------------

So when I try to play Minecraft Multiplayer, I get this screen that says:

Failed to Connect to the Server

Java.Lang.NullPointer.Exception:Group

Playing one of my Singleplayer worlds would crash and say the same crash log like the one above.

If you find any suggestion, please comment. And if it works, thank you so much!

(Here are is image of trying to join a Multiplayer world)

(This thread will be edited if the issue/exception is resolved, or if there were mistakes to viewers, or I will update crash screen and detail in the future)

Quote from webrosc»

Remove mcafee, this is a known issues with minecraft and mcafee and the only known fix is removal of mcafee

To completely uninstall McAfee products, use this tool: http://download.mcafee.com/products/licensed/cust_support_patches/MCPR.exe

Once you have removed and rebooted, try minecraft, if you are sytill having an issue run HJT

Trend Micro HijackThis is a utility that is used to collect diagnostic reports of your computer to help narrow down an issue you may be having. Download: http://sourceforge.net/projects/hjt/

Run the program, choose "I accept", then "Do a scan and save a log file". After a while a text file will open. Copy everything, put the log on http://paste.ubuntu.com and give us the link.

So you mean that when my mom tried to uninstall McAffe, and rebooted, it didn't fully uninstall? (By the way, a few days after I had the error, McAffe was uninstalled and rebooted, but it didn't work, so we had to install McAffe again.) I wonder if there is any way to fix this error, without uninstalling anything