SymptomsI Have Mac Book Air. How Do I Enable CD/DVD Rom in Guest OS?
CauseMacBook Air is shipped without CD/DVD drive, and on Mac OS side in order to get access to CD/DVD you need either to use external USB CD/DVD drive or connect to another Mac's CD/DVD as described in http://support.apple.com/kb/HT2738.
ResolutionYou have several options to enable CD/DVD drive in Guest OS:
1. Connect CD/DVD drive through USB port on your Mac Book Air.
The CD/DVD drive will be detected by virtual machine automatically.
2. Connect CD/DVD drive to your Mac and add it to virtual machine as a USB device.
In this case CD/DVD disks will work normally, but will become non-bootable.
It means you will not be able to install or boot operating system from this disk.
3. If you share CD/DVD drive with some other computer (connect wirelessly to other Mac which has CD/DVD drive),
you will not be able to use CD/DVD drive in Guest OS.
This problem will be fixed in the upcoming Parallels Desktop patches.
Please, monitor the updates on Parallels official web-site http://www.parallels.com