I also doubt the drives have failed, but, they are 2 years old and maybe with updates on my Win 7, 64 Bit they no longer work.
I did try a new drive but it was the same. I needed a DVD-rw on my backup computer anyway.
I have already tried uninstalling the drivers and re-installed the drivers...
I have already tried that. I am going to get 2 new drives.
I have win 7, 64 bit and the drives are older so with updates maybe they no
longer work with the 64 bit version.
I will let you know what I find, it will take a week or more for the new drives to arrive.