there's been a bug in Ubuntu for the longest time now. Wehn you set yourself to autologin you have to enter your gnome-keyring password which is probably but may not be the same as your login password. It has the added disadvantage of not being accessible because it comes up beofre Orca starts talking, and you don't really get auto log in because you still have to enter your password, just in a different spot. It seems to me though, they are in no hurry to fix this bug because it's been around for ever, at least since 8.04. I'm not really sure how to disable it, and you may have to do something in order to get to the password field but I don't think so. If you can get a hold of a pair of eyeballs you may not have to reinstall though.
HTH and sorry for the bad tidings.
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