Laptop password

I bought my toshiba laptop neww about 3 years ago. All of a sudden when I turn it on it will ask me for a password. I never set a password and can't get beyond this page without one. The guy at the store where I bought my laptop says the only way to remedy the problem is to install a new hard drive and remove the battery for a couple of days. My problem then would be, I have no recovery CD. Is there anything else that can be done?