When I edit my controls, they don't seem to save when I close the window. It was working fine until recently when this started happening, can anyone help me?

Trying going into Multiplayer, typing "localhost" into the address bar and let it fail to connect. Then try changing controls.

Had a similar problem some time ago, and this fix was given to me on the Minecraft official forums and it seemed to work.

It works, thanks...

It also helps to delete minecraft from your harddrive(remember not to throw out your saves though) and download it again. That worked for me. I always want inventory to go to the "E" key. Faster and easier than the "I".