I built a new computer and transferred everything over. First, I made a copy of my itunes folder, installed itunes, and replaced the itunes folder with my copy. I found that doing it that way caused itunes to not know the locations of several hundred songs and videos. So I deleted everything, reinstalled itunes, and only copied over the music folder. Now itunes found everything, but all my playlists are gone and it no longer recognizes my iphone or touch, but it will recognize and mount my nano. Any suggestions?