If you lost your password to login in your computer to winxp; here is a small solution-after the booting process is done (or just after switching the computer on) press the button F8. This will allow you to choose between some options.choose safe mode. Once you are in safe mode choose administrator as the user.after logging in right click on My computer and go to manage.go to Local users and groups then r-click on your user name and set password as your wish. you are done.