There are a lot of tools and utilities that can be downloaded and used to recover, reset, retrieve or reveal existing password. Some of them which are worth mentioning are:-
1. Ophcrack - Visit the Ophcrack website, download the ISO image, burn it to a CD and boot off the CD.
After the program starts, select your Windows user accounts. Sit back and wait for Ophcrack to recover/crack the passwords automatically.
2. Offline NT Password & Registry Editor - Similar to Ophcrack, just boot off the CD(download ISO file from the website). Once the program gets loaded you can log in to your Windows account without entering a password at all.
By the way, its always better to create a password reset disk, to reset your password in future.
Get a removable media like USB/CD and log on using the account for which you want to create a password reset disk.
Go to Control Panel > User Accounts > In the Tasks pane, click Create A Password Reset Disk and follow the simple wizard.
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