[ddouglass]

Kathy,
The new Plextors are not guaranteed by Plextor to work with CDG disk format like their older ones were. In fact they used to list that fact in their specs but don't anymore.
Since this is an external I take it you are using a laptop. Have you checked in the new version of Microstudio to see if your internal drive will now work with it? When MTU changed from using the ASPI format to communicate with the drives this opened it up for a whole bunch of previously unusable drives to work with the program.
One other thing I would highly recommend is to update your computer operating system. The newer Microstudio takes advantage of many of the Microsoft upgrades they have put out for us.
This means go to the Microsoft Update page and do the Custom Update. Install everything there to make sure you get everything needed. Be sure and go back to it until there is nothing left to install.
The Auto Update set on your computer or the Express Update from their web page will not give you everything you need. These will only install updates that Microsoft deems as critical.