software or by AutoPlay. See AutoPlay#Devices that are not drives. When Explorer receives notification of a volume change, it performs a number of actions: Checks to see if AutoRun has been disabled through the Registry. If AutoRun is disabled for that drive or drive type, Explorer does not proceed further. There have been bugs in this area. Checks that the root directory of the inserted media contains an autorun.inf file, which might be read. See below. Sends a message to the foreground window. An application which has registered its interest in receiving this message using can respond to this message to halt AutoRun (and thus AutoPlay) at this point. Any application, foreground or not, can also be notified by using the COM interface available in Windows XP and later. Alters double-click and contextual menu behaviours. When a user double clicks on the drive icon in Explorer or right clicks to get a context menu, what happens is fully programmable by settings in the autorun.inf file. Adds an autorun.inf controllable icon and descriptive text to the drive icon. Checks to see if the key is held down. If it is then Windows Vista (and later Windows versions) will invoke the AutoPlay dialog regardless of settings to the contrary. Previous versions of Windows will not continue with the process. Finally, if this point has been reached, either: takes no further action. executes the "AutoRun task", the application optionally specified in the open or shellexecute keys in an autorun.inf's [autorun] section. invokes AutoPlay. Which choice is made depends on the version of Windows in use, instructions from the autorun.inf if available and the type of the media discovered. Changing behaviour Before AutoPlay On Windows versions prior to Windows XP, an autorun.inf file on any drive type will be read and its instructions followed. The AutoRun task, if specified, is executed immediately without user interaction. This includes DRIVE_REMOVABLE, DRIVE_FIXED and DRIVE_REMOTE drive types. AutoRun will work with network drives (the DRIVE_REMOTE drive type) that are mapped to a drive letter. AutoRun will also work with floppy drives that are provided with autorun-compatible drivers. The default Registry settings on Windows versions prior to Windows XP (See NoDriveTypeAutoRun), disable Remote and Removable drives from AutoRun initiation, leaving Fixed and CDROM drive types active by default. Introducing AutoPlay With the introduction of AutoPlay in Windows XP, the final stage action (stage 7 above) for some drive types