If you accept forgotten your administrator password for Windows, y'all can use a Ubuntu Linux live CD or live USB to reset the countersign. This tutorial will show yous how to do that, step by step.

There are many ways to go Ubuntu Linux. Y'all can find more details about that hither.

If you run into any issues or take any questions, the folks at the Ubuntu Forums are very helpful and friendly.
I will not be answering any support questions posted as comments here.

Pace one: Boot up Ubuntu

With the Ubuntu CD in your optical bulldoze or with the Ubuntu USB plugged into your computer, make certain your BIOS is set to boot from CD or USB before your difficult drive. Y'all can commonly enter your BIOS settings by pressing F1, F2, F9, F10, F12, Esc, or Del during bootup, depending on the kind of computer yous accept.


After Ubuntu boots up, you'll be asked if you desire to endeavor Ubuntu or install it. Yous definitely want to but try it at this point.

Step 2: Install the countersign reset software

Installing software on Ubuntu is a bit different from installing software on Windows. Instead of going to a website to download setup files, y'all merely tell the software package manager what yous want installed, and it fetches it for you off some servers. It's a lot like the iTunes App Store or Android Market.

This does presume that you have a working internet connection (wired preferred, but wireless can work, besides). If, for some reason, your internet connexion isn't working on the computer y'all want to reset the password for, you tin also download the chntpw .deb using another computer, transfer it over via USB, and then double-click it to install it.


Commencement nosotros want to make certain we accept the proper software sources enabled to install chntpw.

Go to Organization > Administration > Software Sources


Make sure both the Universe and Multiverse repositories are checked (or "ticked," if you're not American). Click Close and so, when prompted, click Reload.


Wait for the information about available software to reload.


Become to System > Administration > Synaptic Package Managing director

(Note: to those of you who take installed software in Ubuntu earlier, you actually do—at least as of Ubuntu ten.04—have to go to Synaptic to install chntpw. Y'all can't install it through Ubuntu Software Eye).


Press Control-F or click on the Search button to get the search dialogue up. So search for chntpw.

(Note: yous may be tempted to blazon chntpw into the search filter simply it won't show up there, since Synaptic hasn't had time to rebuild the search index for quick filtering.)


Once chntpw pops up in the search results, right-click it and select Marking for Installation.


Click Use, so, when prompted, click Employ again.


Look for the Synaptic to download and install chntpw.

Step iii: Mount your Windows bulldoze

In order for you to reset your Windows password, y'all accept to make the Ubuntu live session know that your Windows bulldoze is bachelor for use. This procedure is called "mounting."


To mountain Windows, only click on Places and then select your drive. It will be listed by the size of the drive (in this instance, fourscore GB).

Step 4: Reset your password

chntpw is a final-based (not signal-and-click) application, so to use information technology, we'll have to open up upwardly a command-line terminal. Don't be intimidated. I'll walk you through the process.


To open up the concluding, go to Applications > Accessories > Terminal

I'm going to be offering a lot of explanation for those who aren't experienced with the last and commands, but if you want to just skip over all that stuff, experience free to just pay attention to the terminal commands and ignore the explanations.

cd /media/493D9CB55373C3DD/Windows/System32/config/

First, you're going to cd (change directories) to the right Windows directory.

Start typing cd /media/ and then hitting the Tab key, and it'll autocomplete with the address of your mounted Windows bulldoze.
Then type W and hit Tab again to get to either Windows (Windows 7) or WINDOWS (Windows XP). Yep, the terminal is case-sensitive, then upper- and lower-instance matters!
Blazon South or s and hit Tab once more to get System32 or system32 (once more depending on whether it's Windows vii or Windows XP—I forget which information technology is for Windows Vista).
And practice the aforementioned for config.

Tab completion makes things a lot simpler, then you don't accept to type every single word out. It also avoids the whole typo issue, in instance you aren't a skillful typist.

Once you've gotten to cd /media/name-of-your-windows-bulldoze/Windows/System32/config or cd /media/proper name-of-your-windows-bulldoze/WINDOWS/system32/config, hit Enter.

sudo chntpw -u username SAM

Yous should and then type in sudo chntpw -u username SAM, where username is your actual username. For example, if your username is susan, information technology should be sudo chntpw -u susan SAM

Subsequently you blazon that in, hit Enter, and you'll encounter a whole bunch of final output, most of which you lot can ignore:

chntpw version 0.99.5 070923 (decade), (c) Petter N Hagen
Hive

name (from header): <\SystemRoot\System32\Config\SAM>
ROOT KEY at first: 0x001020 * Subkey indexing type is: 666c
Page at 0x7000 is not 'hbin', bold file contains garbage at stop
File size 262144 [40000] bytes, containing 6 pages (+ one headerpage)
Used for data: 260/20240 blocks/bytes, unused: 9/4144 blocks/bytes.

* SAM policy limits:
Failed logins before lockout is: 10
Minimum password length : 4
Password history count : 4
| RID -|———- Username ————| Admin? |- Lock? –|
| 01f4 | Ambassador | ADMIN | dis/lock |
| 01f5 | Guest | | dis/lock |
| 03e8 | susan | ADMIN | |

———————> SYSKEY Bank check <----------------------- SYSTEM SecureBoot : -1 -> Non Set (non installed, good!)
SAM Account\F : 0 -> off
SECURITY PolSecretEncryptionKey: -one -> Non Set up (OK if this is NT4)
Syskey not installed!

RID : m [03e8]
Username: susan
fullname:
comment :
homedir :

User is member of i groups:
00000220 = Administrators (which has 4 members)

Account bits: 0x0214 =
[ ] Disabled | [ ] Homedir req. | [X] Passwd not req. |
[ ] Temp. duplicate | [X] Normal business relationship | [ ] NMS business relationship |
[ ] Domain trust ac | [ ] Wks trust act. | [ ] Srv trust human activity |
[10] Pwd don't expir | [ ] Auto lockout | [ ] (unknown 0x08) |
[ ] (unknown 0x10) | [ ] (unknown 0x20) | [ ] (unknown 0x40) |

Failed login count: 0, while max tries is: x
Full login count: 100

This part is important, though:

– – – – User Edit Menu:
1 – Clear (blank) user password
2 – Edit (set new) user password (careful with this on XP or Vista)
iii – Promote user (brand user an administrator)
(4 – Unlock and enable user account) [seems unlocked already]
q – Quit editing user, dorsum to user select
Select: [q] >

I would highly recommend typing 1 to blank the password instead of editing the countersign. Afterwards y'all type that, hit Enter, and you should see

Password cleared!

Hives that have changed:
# Name
0
Write hive files? (y/n) [northward] :

Type y and hitting Enter to confirm the alter. Once you see

then yous're done.


Now yous can reboot, and you can log into your admin account with a blank password. Once you're logged in, you tin become to the Control Panel to modify your password to something else—something you lot can remember.

If you're curious, you can come across an older version of this page.