Decided to install Vista Ultimate to brand new Hard Drive. discovered I needed a DVD drive as well. Installed a LITEON SHD 16P1S. Vista loaded without incident as did MS Office XP, MS Project and MS Visio. Installed a few other apps (BOINC, etc.) from downloaded files and then tried to install Visual Studio 2005 Beta. Although the Beta period is over, I wanted to have a base for the VB SP1 pack. When the install got to the VB install, it stopped. No errors displayed and then finally an advisory to "Place Disk 1 in the CD-ROM drive". Looked at "Computer" window and discovered that the DVD/CD-ROM drive had "disappeared from view. Also not in the hardware listing on the control panel. Executed shutdown and then started uip. DVD/CD-ROM drive back in normal operation. Tried another VB install and it choked, drive disappeared in same place. Shutdown and reboot - drive is back. then it occurred when I inadvertently opened the drive door while accessing "Computer" window from the start menu. The DVD/CD-ROM drive is installed as a master on the second IDE port - nothing else on that port. The drivers came from Vista. I looked at LITEON site and they have firmware available but no drivers that I can find. Anyone have any ideas. I ran Vista Beta up until end of January with no major problems, but didn't have the DVD then.