I changed the name of my administrator account but kept the password the same. Now i cannot login. I do not have a recovery disk or vista os disk to boot from. How do i bypass to login. Thanks.
Reboot and login to this account and change your current account as needed to regain access - even if you need to return to the old username (but that shouldn't be necessary if you change it in the proper way). Add another Administrator account for emergencies like this. Then after you've confirmed everything is back to normal, disable the built-in Administrator account (as it presents a security risk and shouldn't be used except for emergencies) where it will remain until needed again.