can any1 help???????????????? cant set printer up?

Can any 1 help???????????? how do i get my computer to recognise my printer.
I have install the disc to the point where it has to find the printer.
When i turn the printer on for it to find the port it is plugged into, the bottom right of the screen shows a usb symbol but it says unknow device. It doesn't recognise the cables attached to a printer.
This is as far as i can get. I've even loaded all the disc when it says add printer later still wont work.
The printer loads straight away on any other computer (with the same cable) just not on to this computer. when you go into device manager it says no driver install even though the set up disc says set up successfull. Its on xp and its a hp printer. I have also tried my own printer and this does exactly the same thing.