laptop usb ports don't work>>>

I purchased a dell laptop and the usb ports don't work: the are when i go to system and check the hardware/ everythings fine. but when i plug something to the ports they don't recognize what i hook to them. the laptop is a dell inspiron 1150? if someone has been down this route before,feel free to comment. I'm trying not to get another motherboard. I don't know the exact specs on the laptop at this time, but i will have them posted later.
thanx