I'm a newbie here so maybe this has been discussed in past threads. I recently replaced one of my older CD-ROM drives with a Sony DRU 720A in my Dell Dimension 8200. When I put the installation CD for Nero Express in the drive, a screen with all ?????? comes up. The drive is fussy about which CDs and DVDs it wants to read. It'll read some but not others. For sure, it can't read the installation CD. What gives? An installation problem or... ?