I have a problem that really stumps me.

I
bought a Seagate external hard drive (3 Terabyte).  It has a simple USB
interface (2.0 and 3.0).  It is supposed to start the installation
software on the drive and set itself up.

I
did this on my 3-year-old Toshiba laptop running Vista and it worked
flawlessly.  Then I plugged it into my 3-year-old Dell desktop running
Vista.  It didn't start up by itself..  So I found the drive under My
Computer.  I could see the files on the drive.  When I click on the
setup file, it says it cannot find the drive or the file.  But it was
showing me the drive and the files on it! I could click on one ASCII
batch file and I could see the file contents. 

It seems to not want to execute .exe files.

I tried pasting a file on the drive; it says the source file does not exist.

I have tried looking all over the Web to no avail.

All
other USB devices are working fine.  I tried plugging the drive into
the front and back USB ports because I thought I once heard the front
USB slots don't have power or as much power as the back slots.

Any ideas?