Click on the picture here (taken from http://www.redflagdeals.com/forums/showthread.php?p=3976250): The CMCs will have "Open" and "Lock" in Times New Roman. LOCK OPEN = (CMC) (I would tend to avoid PAP6 serials, personally) LOCK OPEN = (prodisc) (I tend to favour CMC Verbatim 16x dvd+rs, with the exception of the PAP6 serials) You can also look at the serial in the inner clear hub of the DVD's. Prodisc serials have a + or - (+ since they're DVD+R's) in them. CMC serials often start with "PAPxxxxxxx". Also ensure you're changing the booktype to "dvd-rom". Visit http://forum.slysoft.com/showthread.php?t=476 (read step 3).