I try to log onto a server and my singleplayer, and I crash EVERY time, but as far as I know only with 14w25b

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here
log into a server
What actually happened was...:
Describe what happened here
Crash
Steps to Reproduce:
1. open up 14w25b
2. open up a world
3. ...