I turned off auto-run on my Windows desk the other day. Auto-run is a feature which permits the operating system to start an application when a disc is inserted into the CD-ROM drive. Some discs use the feature to start the music player, or a demonstration, or to violate constraints start an installation process. notes

Windows will no longer be notified when you insert a new CD.

I don’t comprehend why AutoRun needs to be enabled for the drive ready event to fire — unless there’s no drive ready event.