After creating a nice Hyper-V R2 cluster with 4 nodes and installing Virtual Machine Manager 2008 R2 I was ready to deploy a Windows 2008 R2 Server. Adding the virtual machine, and configuring it for fault-tolerance, I was excited to start installation. I mounted an ISO file with Windows Server 2008 R2, and started the virtual machine.
Booting the virtual machine from the ISO file, I passed the localization information, and got the following error message:
"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.
Note: If the Windows installation media is in the CD/DVD drive, you can safely remove is for this step."
We also tried burning the ISO file to a physical DVD , and booted directly from the DVD (inside the virtual machine). That worked out.
Interestingly the ISO file does not work when mounted in the virtual machine, but it works when burned to DVD. Other ISO files with Windows Server 2008 R2 worked, also when mounted.
Seems like the ISO file was corrupt, even though it worked somehow when burned to DVD.