I rooted my new Kindle Fire HD, an accidentally using ES File Explorer, change the "system" folder permission to only read and write, and my kindle got laggy so i turn it of and now it says that is not able to boot..... any solutions?
You would have had to use adb to root your device one way or another. Either by installing the android sdk (and all its files) or rooting manually. I did the semi-automatic rooting method using that emu program, and my device was rooted (took a few hours of trial and error though!)