Okay, thanks for that bit of information. I guess that is what I will have to do also. I don't think I mentioned the model number of mine but it too is a 2100 (CRW21001X). Maybe Roxio figures no one has any of these old Yamahas since Yamaha stopped selling CD burners (they did, didn't they, I forget). So they don't support them anymore.
Anyway, as an update and evidence to what you say that for some reason this is affecting Yamaha 2100s, I shut down my computer July 3rd, didn't even use it on the 4th, then started it today the 5th and Toast does now see my external. Unfortunately, as in your case, if I try to use it, it just hangs (spinning beach ball).
So I guess it is back to 7.0 What a pain.
Jonathan M. Miller