My old 250 Gig H Drive on my new laptop seems to function but my new laptop does not seem to see it

…Hi …I have a 250 gig external H.Drive wich was on my P4 with Xp Pro…and it seems that if i want to set it up on my new toshiba portable 8 Gig Live mem…750 Hdr. with windows 7 …i would have to get additional drivers …or whatever …inst prog…is there anyone who knows what i have to download and where on this site

         it is a WD My Book Essential edition 250 Gig external Hard drive wich i bought about 5-6 years ago…I had registered it then…but cant be more precise for now…

        i tryed pluggin it in but my laptop does not seem to see it

On the Windows 7 computer, if you check on disk management, is it recognized there?

In Windows 7 does the drive show in Device Manager? It might be a driver issue 5-6 years is before Windows 7 came out.