I have an old Dell Inspiron 9400 laptop with an internal DVD-ROM drive. Each time I burn a CD or DVD using the ImgBurn program I can't burn another one until I reboot my laptop, or sometimes it will do the burn part but not verify. This is the way it happened just now, as I was creating these screenshots. I am running Windows 7 Pro, as the screenshot shows. Once this happens I can't see the drive in Device Manager either until I reboot the laptop.