virtualbox.org

I am running a windows 7 Host and many Windows 7 guests.
One of these needed to write to a CD/DVD but I am unable to find the settings for the 'passthrough' quoted in the help file section 5.9. I thought this was definable in the GUI.
Where?

CD/DVD passthrough is available in the Storage settings for a virtual CD/DVD drive. The option is only available when the virtual drive has been mapped to a host drive.

Thanks mpack.
The step I was missing was the selection of the host drive before shutting down and going to the settings for the storage.
All OK now