DVD-RW won't erase CD-RW's or DVD-RW's

I have a NEC DVD-RW model ND-3500AG which supports just about every type of cd or dvd including CD+RW, CD-RW, DVD+RW and DVD-RW. It will write the the cd's or dvd's o.k. but using re-writable cd's or dvd's it will not erase the data. It treets the RW cd's and DVD's the same as CD-R's and DVD-R's. I have the latest drivers installed. I have tried uninstalling the DVD drive in the device manager and letting windows re-install it. I can't seem to get it to write over using re-writable disks. Any ideas on something that I might be missing?

 

It's nothing you've done, I've got the same make and model of dvd burner (Right now i'm using a pioneer dvd burner, and so far no problems ) and had the same problems, I've had some dvd rw's it wouldn't erase.
Those nec burners aren't worth the investment.

 

Thanks for the reply hugh. At least now I can stop beating my head against the wall trying to get this thing to erase the way it should.