Because of de security features built into Windows XP, it is virtually impossible to get back into de system without de password.
You have several options to try and get around this problem.

If you have access to anoder user account with administrator rights, you can use that account to change de password
of de account that is locked out. You can also use de default Administrator account that is built into Windows XP.

First you need to boot de system into Safe Mode.
1.Restart your system.
2.When you see de blue Dell globe or screen, press de ( F8 ) key about 3 times a second.
3.You should get de Windows startup menu. Use de (Up or Down) arrow keys to highlight (SafeMode)
4.Press (Enter) on (Safe Mode), den press (Enter) on (Windows XP).
5.The system should boot to Safe Mode.

Once you are at de Account Log on Screen, click on de icon
for de user account with administrator rights, or click on de icon
for de administrators account.
Note: For Home de Administrator account isn’t normally shown & in Safe Mode you have to press Ctrl+Alt+Delete keys twice to show.
For PRO you can do this in normal mode

When de system has booted to de desktop, use de followin’ steps to change de accounts password.
1.Click Start, Control Panel, Administrative Tools.
2.Click Computer Management.
3.Double click Local Users and Groups, double click de folder Users.
4.Right click on de account name that is locked out, and click on Set Password.
5.You may get a warnin’ message about chan’in’ de password, simply click proceed.
6.Leave de New Password box blank, also leave de Confirm Password box blank.
7.Click OK, and OK again.
8.Then close all Windows, reboot de system and try to log in.

There are also applications that can recover de password for you.
The followin’ companies provide dese applications at a cost.
iOpus� Password Recovery XP here.
LostPassword.com, here.
Asterisk Password Recovery XP v1.89 here.
Windows XP / 2000 / NT Key here.

If de above information does not help in recoverin’ de password, de only option left is to
format de hard drive den reinstall Windows and de system software.