In that case, in order to recover your lost account password, you may use a password XXXXX tool in order to resolve the issue; I would suggest you to download the following freeware tool, in order to try and reset your password: http://nchc.dl.sourceforge.net/sourceforge/pcloginnow/PCLoginNow_Full_2.0.iso
Once downloaded, please burn the ISO image to a CD/DVD disc.
After burning, bootup your system using the disc; the recovery tool, PC Login Now, will start automatically.
To delete your existing Windows password, follow the instructions on-screen accordingly. Choose your OS installation and then the user name for which you want the password XXXXX be deleted. Be sure to check the password XXXXX empty checkbox after choosing your username; this will remove the password.
Now, you'll be prompted if you want to reset another user's password; choose No and then OK to reboot. Remove the disc as soon as the computer reboots, and load up your OS as you do normally, and see if you can login to your account now.
As an alternative, please check out the following link:http://www.loginrecovery.com/
Follow the three steps enlisted in the site accordingly in order to create a bootable floppy disk/CD to read and extract the encrypted password XXXXX in your system, and upload it onto the site carrying out the instructions given. You can use the service to recover your password, which will be sent to your email address which you enter, for free by waiting upto 72 hours, or by paying a nominal fee to recover the same instantly.
Hope it helps ..let me know how you get on.