Parceling out the details can lead those that want to help off track.
As to your question. J is likely your usb drive so the item is there and not on the computer's hard drive.
Vista Home Premium 32 bit with Vista SP2
Inserted a flash drive into the PC. Showed a "J" drive
My Norton Internet Security detected W32.Downandup.B and quarantined it.
Besides quarantining the file, my security also seemed to indicate fixing 2 registry items
It showed the infected file as
So does this mean my Internet Security detected it on the Flash Drive? Or on my hard drive?