Windows XP lets you create a special disk to help you if you forget your password.
To create a password recovery services disk you'll need a formatted floppy disk in the floppy disk drive. From the main window, click on the Start Menu, go to Control Panel, and then User Accounts. Next, click on your user name. To the left you will see a related tasks option. Click on "prevent forgotten password". This launches the password recovery wizard.
Follow the instructions from the password hacking wizard to create the recovery disk. Then label it and put it in a safe place.
To use the password recovery wizard, click on your user icon on the logon window and then click the green arrow, just as if you knew your password. This will launch a dialog box which will tell you how to use your password recovery disk.
This is not something you want to try to do when you realize you've forgotten your password. To create the password recovery disk, you need to know your password. Ideally, you should make a password recovery disk as soon as you create a user account.
Or In Step by Step:
Prepare a blank disk, or a thumb drive. Follow the following steps:
1. Click Start, go to Control Panel.
2. Look for User Accounts, go inside and look for your account name.
3. Under Related Task (left), click Prevent a forgotten password.
4. Follow the steps until you the Finish button.
You are done, eject the disk or thumb drive and make sure you remember where you keep it.