The beta version of imgburn works perfectly on everything I have tried so far. In particular, it reads store-bought CD's, CD+r's and even CD+rw's on both my disc drives. It writes as expected. I have not tried anything with DVD's as yet. Thank you for this assistance and for the imgburn program, which I have shamelessly used for free for years. I'll be sending you a small gift as soon as I figure out how to work paypal.
Paul in San Francisco