Now it is time to use my Passport and?

My computer crashes and I had just  bought the Passport and only ran it once.  I plugged it in and expected an extra drive to appear with my old computer on it.  Is there something else I need to do?  There were a few files on it but nothing that meant anything to me?  Does anyone have any advice for me?  I really need the files.  I have the hard drive removed from the laptop  (the fanblower was the problem) but can’t transfer it easily with a USB connection like last time.  Any help would really be appreciated.