Can't get in, i don't know the reason? HELP :(

Put the summary of the bug you're having here
I am not sure what happend actually and what is the reason but i just tried to go in multiplayer server and it just crashed.. Tha same happend with my friend here... But this applies to 1.7.10 for the stuff that you choose version says that he can not find it ...

Describe what you thought should happen here
What should happend is it should pop up, i tried to log on in the multiplayer server but didn't help.. i just got crash message...

What I expected to happen was...:
It would woprk, and it won't crash..

What actually happened was...:
It crashed and i couldn't log in on the server....

Describe what happened here
When i logged in the client, and pressing (trying to connect the server) As I try to connect to so win the that it crashes, and it does not happen in other versions.

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