If unfortunately, you don't have alternate admin account or password recovery disk, but you don't want to reinstall the OS, a Windows password recovery (eg. Windows Password Unlocker)software will be the optimal choice.
Method 1: Log into an alternate account
Often many users will leave the administrator account alone and/or have other accounts with administrator rights. If you're not logging into the computer as administrator or have other accounts follow the below steps to reset your other accounts password. Reboot the computer into Safe Mode. Additional information about getting into Safe When logging into Safe Mode you should be prompted with an option to what account you wish to use. Select the Administrator account. If prompted for a password try simply pressing Enter on the keyboard for no password. If this does not work, try other passwords you may have used. If you're unable to log into the Administrator account skip to the next suggestion.
Once you've logged into the Administrator account open Control Panel and User Accounts.In User Accounts select the account you wish to change the password for, click change password and then enter the new password or click remove the password to remove the password from the account.
Method 2: Using the forgotten password diskette
If you have forgotten your Windows XP password, however have created a forgotten password diskette earlier to use the diskette follow the below steps.
1 At the Windows XP login prompt when the password is entered incorrectly click the reset button in the login failed window.
2 Insert the password reset diskette into the computer and click Next.
3 If the correct diskette Windows XP will open a window prompting for the new password you wish to use.
Method 3: Using the Windows Password Recovery Tool---Windows Password Unlocker
If you have neither other accounts with administrator rights nor passwords reset diskette, take use of the third part password reset tool. There are many related tools that can help to remove/reset/bypass widows passwords(including Windows NT 4.0, Windows 2000, Windows XP, Windows 2003 Server, Windows Vista and Windows 2008 Server,ect). Here, Windows Password Unlocker is highly recommended. It has been tested on all kinds of Windows Systems, and the performance is always perfect. Morever, it keep the whole data intact but the login password. Just below steps, the previous password can be removed without login the locked computer.
1.Download Windows Password Recovery tool from Password Unlocker Official site http://www.passwordunlocker.com/products/wpu.html .
2.Decompress the Windows password unlocker and note that there is an .ISO image file. Burn the image file onto an blank CD with the burner freely supported by Password Unlocker.
3.Insert the newly created CD into the locked computer and re-boot it from the CD drive.
4.After launched the CD, a window pop up with all your account names(if you have several accounts); select one of the accounts that you have forgotten its password to reset it. Just one press, you have removed the password.
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