"CD/DVD drive device driver is missing" while trying to upgrade from XP to 7

Let me first say, that this is MOST often a bad image, whether the source ISO (download especially) or the method in which its burned.  This has been resolved many times by either re-downloading the ISO (even using a download manager) and/or by burning at the slowest possible speed of the software/burner.  The fact that you have tried USB as well tells me that it may be the source ISO.  Did you download it?  Do you have another system you can install it on?  Can you install it "virtually" (Virtual PC, VirtualBox, VMWare, etc.) to show the ISO is good?

On some systems, the CD/DVD drive is actually controlled by a special controller, for which the proper Windows 7 drivers must be loaded, but the D620 doesn't have any "special" controller that would cause this.

My system is : Latitude D620   While trying to upgrade from win XP win 7, actually not upgrade but clean install, I boot from the Win7 DVD. Everything starts normally, I choose language settings and press "install now".   Then this message appears "a required CD/DVD drive device driver is missing. If you have a driver floppy disk, cd dvd or usb flash drive please insert it now"   I googled, and read hundreds of opinions and experiences regarding this matter, bad dvd burn, IDE controller incompatibility, that you cannot go directly from XP to 7 etc etc   Please advice. Up to now I tried every conventional possible solution, like DVD firmware upgrade, reburn 4 times from different burning software, install from USB flash drive (that produced exactly the same error message).   The win7 version is 32bit ultimate retail.   Thanks in advance   Panos

I just did a Windows 7 64-bit install on a Dell D620 this weekend. And it worked perfectly without the issue you mentioned.

I didn't see such problem in upgrading any version of windows to any other one. Do you see such error when you want to install a fresh windows 7 without upgrading it?