I had to use an .iso USB to upgrade from 12.10 to 13.04 Ringtail. Great results, except the USB stick install app asked me to provide an identity so I provided the same one I used for 12.10 . Unfortunately it overwrote my other identity with a fresh one, so now I have no ownership of all my previous profiles, etc. A dumb mistake, but is there a way to take ownership of my previous user identity and merge it with the current?