Pheeeew, this still works. I was having issues with Windows and had to re-install, and therefore had to reinstall steam and rocksmith. I kept getting the arrrrggghhh error (lol) and had tried almost everything. (I was trying to see if I could have steam on an SSD seperate from the drive so thought this was the issue. 2 reinstalls of steam later and Google was my friend. After the 3rd install I followed the instructions above and low and behold, it worked. Thank you, thank you, thank you