Welcome to the forums.
When you say you need to reset a password, is it for a guest?
What is the version of Windows? XP Pro/Home when not in a domain, can be booted into safe mode, and then you can log in as Administrator, and reset a password.
Have you looked for a Windows password reset utility?
I'd start with Google...
Jase McCarty
http://www.jasemccarty.com
Co-Author of
VMware ESX Essentials in the Virtual Data Center
(ISBN:1420070274) from Auerbach
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