I have on my computer K Probe, Cd Diagnostic, CD/DVD Diagnostic as well as Cd Speed. I don't use Doctor since it contains a trojan horse/spyware as reported by Norton as well as other spyware checkers, so that one is out. I'm not really sure why my drive behaves in the way it does with cdrw's. All I know is what it does, I eject the disc and it will read fine the second or third time. I doubt the drive is bad since I burn on a daily basis, it could be a mismatch between the drive and the cdrw's which are: Maxell/Made by Mitsubishi, TDK/Made by Plasmon Data Systems, Memorex/Made by Infodisc and Lite-On/Made by CMC Magnetics/Yikes! The dreaded CMC! I always erase using the full erase method. Not a big deal really, I was just tossing my comments out there to see if anyone else has run into this unusual condition, but I will scan these discs for damage as soon as possible.