Java.nullpointer

Put the summary of the bug you're having here

What I expected to happen was...:
that i can get on my server

What actually happened was...:
I have a rent server and i can´t get on it because minecraft have a problem like this

[09:26:15] [Client thread/INFO]: Setting user: diehex
[09:26:15] [Client thread/INFO]: (Session ID is token:b2b90134433e435f86cc0ddd33d50b5a:727a140b534147e88d260ae5aae574dd)
[09:26:18] [Client thread/INFO]: LWJGL Version: 2.9.4
[09:26:18] [Client thread/INFO]: Reloading ResourceManager: Default
[09:26:19] [Sound Library Loader/INFO]: Starting up SoundSystem...
[09:26:19] [Thread-6/INFO]: Initializing LWJGL OpenAL
[09:26:19] [Thread-6/INFO]: (The LWJGL binding of OpenAL. For more information, see http://www.lwjgl.org)
[09:26:20] [Thread-6/INFO]: OpenAL initialized.
[09:26:20] [Sound Library Loader/INFO]: Sound engine started
[09:26:23] [Client thread/INFO]: Created: 512x512 textures-atlas
[09:26:36] [Client thread/INFO]: Connecting to 94.250.206.97, 25565
[09:26:36] Server Connector #1/ERROR: Couldn't connect to server
java.lang.NullPointerException: group
at io.netty.bootstrap.AbstractBootstrap.group(AbstractBootstrap.java:80) ~[netty-all-4.0.23.Final.jar:4.0.23.Final]
at ek.a(SourceFile:264) ~[1.8.4.jar:?]
at awz$1.run(SourceFile:59) [1.8.4.jar:?]

Jave is new installed, minecraft too.

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