The bad thing is you forgot windows password. And the worse thing is you didn't have a CD drive for some reason. But the good news is that there are still some programs that can help you!
Before using windows password recovery softwares, you should know the following basic things of windows password recovery:
Password Hash: When you type in password in Windows XP, NT, 2000 login windows, windows operating system converts (encrypts) these passwords in something like this: 7524248b4d2c9a9eadd3b435c51404ee This is called password hash and this encryption is done using high level encryption schemes.
SAM Files: In windows Operating system, these password hashes of every user account are stored in SAM Files. When user types in password on login screen, windows compares this SAM file contents with typed password and allows access (if matched). So, it is necessary to get these SAM files, if you want to recover your password.
Problems with SAM Files: There are two problems with recovering passwords from SAM files:
This SAM File is locked during active windows session and hence cannot be accessed without booting. Thus, you have to boot system from another Operating System (NTFSDOS or Linux usually) and then copy SAM File to floppy drive or convenient external device like USB flash drive.
Even if you copy this SAM file, since the SAM File is in encrypted format, you can’t see passwords in plain text form and so you have to recover (actually crack) passwords. For this purpose, either Dictionary or Brute force attack is implemented. But it still take a very long time if you password have many characters. The most convenient windows password recovery way is to use some programs to change the corresponding position in SAM file. Then you can log in again with no password.
Nowadays, most of windows password recovery tool is to boot up with CD. Fortunately, there are still a few windows password recovery tool support USB flash drive recovery. But you have to pay for some. Enjoy these windows password recovery tool!
Difficulty: A little Difficulty.
But I had some problems with it doing an infinity loop when I tried to use Kon-Boot from a USB flash drive (worked fine on the same box from a CD). Then I find an article guide you to use it correctly.Read on Using Kon-Boot from a USB Flash Drive: Bypass those pesky Windows and Linux login passwords completely.
Distribution Home Page: http://ophcrack.sourceforge.net
Minimum Flash Drive Capacity: 1GB
Persistent Feature: No – Doesn't need to be
USB Ophcrack flash drive creation essentials:
- Windows Computer (Windows XP or Vista)
- 1GB or larger flash drive (fat32 formatted)
How to Create a bootable Ophcrack flash drive:
- Download the Ophcrack XP Live CD ISO
- Insert your USB Flash Drive
- Download and run tazusb.exe then follow the onscreen instructions until the install has finished
- Create a folder named vista_free inside the tables folder on your USB Flash Drive
- Download and unzip the tables_vista_free. zip to the tables/vista_free folder on your USB Flash Drive
- Reboot your PC and set your system to boot from the USB device
If all goes well, you should be booting from the USB stick into a mini Linux environment. Ophcrack is launched automatically after the system has booted. You should now be able to recover both Windows XP and Windows Vista login Passwords using this single USB tool.
3. Windows Password Reset 7.0 Pro
Windows Password Reset 7.0 is professional Windows password recovery software to reset lost Windows administrator and user passwords for you to log into Windows instantly without reinstalling the OS. It supports to reset passwords of all Windows versions, like Windows 7, Windows Vista, XP, 2008, 2003 and 2000, etc. You can burn this Windows password recovery software onto a bootable CD/DVD, USB drive or a floppy drive to use it to recover the password either in a household, business or a government environment. With this windows password recovery tool, instead of locked out of your computer, you are able to login Windows with a blank password (no password). It is also recommended by professional PC support.
Hope these tool I found can give you a hand to reset windows password with USB flash drive! 😀