no way to find it out but to reset it.
try "windows password reset"
you can reset your password easily with it.
Step1. Find your Windows Vista installation disk, insert it into the CD-drive, restart the computer and enter BIOS. On the Boot Device...
does it work?
you can google it to see if there are any program that can help you
you should try some recovery tool like "windows password reset".
it can reset your password to "blank" easily.
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