Why Finder Won't Let You Eject Disk Images (and How to Fix It)
by Jake Peterson from Lifehacker on (#5TS7M)
It's frustrating when your computer doesn't do what you ask. If you no longer need a disk image connected to your Mac, and you go to eject it, it can be frustrating to be met with an error: The disk couldn't be ejected because the Finder is using it." Using it for what?