Not everyone created their Vista password reset disk which means your account in Vista is locked and you have no access unless you have another user account in Vista that is using an administrator account. Try to login using another administrator account in Vista (it can be another admin user account that you’ve created before or the default but hidden administrator account that you’ve enabled), select Start button, type lusrmgr.msc in the Search box and click Enter key in your keyboard. The Local User and Groups console will be displayed. Select “Users” in the left pane. Right-click the account that you need to reset the password for, and click Set Password. Type and confirm the password.
Note that resetting the password in Vista using another administrator account has impact: You will lose access to encrypted e-mail messages, stored password for websites and encrypted files on that account that you reset the password for. If your emails and files are not encrypted, you are not affected.