The Bottom Line
The Kon-Boot password hacking tool has to be the easiest, and fastest, free Windows password recovery tool I've used. It's actually a password reset tool as many of these programs, like ONTP&RE and PC Login Now, are.
However, Kon-boot works in an entirely different way than those other Windows password reset/deleting tools so it's an excellent alternative if they haven't worked out for you.
- Easiest password reset tool available
- Software is freely available
- ISO image is smallest of any free password recovery or reset tool
- No access to Windows or knowledge of old password is needed
- Works with Windows 7, Windows Vista, Windows XP, and some Windows Server OS's
- Access to another PC required to burn ISO file
- Occasional issues with Windows 7 in my experience
- Not supported on 64-bit Windows operating systems 
- Kon-Boot will temporarily remove the password on nearly any 32-bit version of Windows including Windows 7, Windows Vista, and Windows XP.
- No installation is required - all password resetting is done from bootable disc or flash drive.
- Kon-Boot is easy and fast, making the password reset task in Windows one of the most efficient I've seen.
- ISO download is very small, a stark contrast to the huge download required for a true password recovery program like Ophcrack.
Guide Review - Kon-Boot v1.0
Kon-Boot v1.0 is probably my favorite Windows password reset program, mainly because it's so fast and easy to use. I'd rank it higher among the other options available but it doesn't support 64-bit operating systems and is hit-or-miss in Windows 7.
However, since it works so differently than Offline NT Password & Registry Editor and PC Login Now, Kon-Boot is an excellent alternative if you need your Windows password reset and both of those free tools haven't worked for some reason.
Kon-Boot requires a few post-cracking steps to be a real Windows password reset solution but nothing required by this amazing program is too difficult for anyone with the very serious problem of being locked out Windows.
How To Use Kon-Boot
To get started, visit the Kon-Boot site by clicking Visit Their Web Site above the User Reviews at the bottom of this page.
Once there, scroll toward the bottom of the page. Look for the section titled "Download FREE Version."
Click on MIRROR #1 link. This will take you to a page where you can download the kon-boot1.1-free.zip file. This file is extremely small so it shouldn't take more than a second or two.
Once downloaded, extract the files (the password is kon-boot) which will create several folders with yet more ZIP files. Locate the CD-konboot-v1.1-2in1.zip file and extract it, creating the CD-konboot-v1.1-2in1.iso file.
Note: I know the file names make it look like you're using Kon-Boot v1.1 but it's actually v1.0, which you'll see noted when you run the program.
Burn this ISO file to a disc - a CD is fine. Burning an ISO file is different than burning a normal file so if you need help please see How To Burn an ISO File to a CD.
After creating the disc, boot from the disc by rebooting your PC with the disc still in the drive. Kon-Boot will start automatically. When you see the Kryptos Logic logo, hit any key. The rest of the process is automatic.
Once Windows starts, just log in to your account with a blank password. It's also possible that Windows will just log in automatically and skip the password asking process. Either way is fine.
Unlike other password reset tools, this isn't the end of the story. Kon-Boot has created a special situation where you can access your account but this goes away next time you start your computer. Unless you want to use Kon-Boot to login to Windows every time you start your computer, you'll need to change your password. Unfortunately, Windows will not let you do that from within your account right now.
To solve this problem, create an administrator account, log off, log on as the administrator, and then reset your account's password from the account you just created. Once you've done that, you can remove the disc, restart your computer, and login to your own account with the new password you created. Feel free to delete the administrator account you created to reset your password from.
Once this is all done, be sure to create a password reset disk so you can avoid using Kon-Boot ever again!
Having Problems Using Kon-Boot?
Also, be sure to read through my Windows Password Recovery Programs FAQ for answers to the most common questions I get about these kinds of programs.
 Kon-Boot v1.0, the free version I've reviewed above, does not support 64-bit operating systems. However, Kon-Boot v2.2, available for $18.99 USD here, is an updated version and according to the documentation available does support 64-bit versions of Windows. There are probably various other stability improvements as well. I have not personally tested v2.2 and do not recommend you purchase the program unless you've exhausted your free password recovery options first.