Sorry, read the following posts more closely than your original one!
This may be nonsense, but when I originally connected my external box I had the same problem. I already had Nero installed on my system but it wouldn’t “see” my drive, neither would Windows.
So - I installed the complete package from the CD (Sonic MYDVD) that came with the drive, and Windows/Sonic recognised it straight away. Then I uninstalled all the Sonic software (as I prefer Nero) and then Nero & Windows recognised my external drive. I couldn’t find any specific drivers on the CD by exploring, so I have no idea why this worked for me, but it did.
Hope something works for you!