First of all, dont tamper around with the .minecraft folder and it's contents if you don't know what you're doing. Secondly, 1.6.4 is a fairly old version, isn't it time to upgrade?
Anywhere I go I see 1 of the 2 things mentioned below.
12 year old kid with dumb stolen intro and only posts minecraft pvp with bandicam recording software.
6 year old kid who shouldn't be on youtube at this age. Shoves camera into mouth trying to speak to the audience/viewers and uses camera to record him "building a dirt house"
DON'T GET ME STARTED WITH ETHANGAMERTV
Spoiled child with an annoying voice, whose parents do anything he desires. like robots.