Eliminating The Windows Password. 

If you are annoyed by Windows 98’s prompt for a password each time you start up your computer, you can quickly eliminate this step.

Click Start, Settings, Control Panel. Double-click Passwords. Click the Change Password tab. Click OK. In the Change Windows Password dialog box, type your password in the Old Password box, leaving the New Password and Confirm New Password boxes blank. Click OK. Click the User Profiles tab and verify that the following option is selected: All Users Of This PC Use The Same Preferences And Desktop Settings. Click Close. Shut down and restart Windows.

Access Manager - More info

     If the above options do not provide enough security for you, download Access manager for Windows.

Access manager provides much more security than standard ways in Windows.

More info

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