Download Autorun Usb

[Eddie Boyum]

AutoRun was introduced in Windows 95 to ease application installation for non-technical users and reduce the cost of software support calls. When an appropriately configured CD-ROM is inserted into a CD-ROM drive, Windows detects the arrival and checks the contents for a special file containing a set of instructions. For a CD containing software, these instructions normally initiate installation of the software from the CD-ROM onto the hard drive. To maximise the likelihood of installation success, AutoRun also acts when the drive is accessed ("double-clicked") in Windows Explorer (or "My Computer").

AutoRun, a feature of Windows Explorer (actually of the shell32 dll) introduced in Windows 95, enables media and devices to launch programs by use of command listed in a file called autorun.inf, stored in the root directory of the medium.

Primarily used on installation CD-ROMs, the applications called are usually application installers. The autorun.inf file can also specify an icon which will represent the device visually in Explorer along with other advanced features.[1]

The terms AutoRun and AutoPlay tend to be interchangeably used when referring to the initiating action, the action that detects and starts reading from discovered volumes. AutoRun is positioned as a layer between AutoPlay and the Shell Hardware Detection service which may help in understanding the terminology. However, to avoid confusion, this article uses the term AutoRun when referring to the initiating action.

AutoPlay is a feature introduced in Windows XP which examines removable media and devices and, based on content such as pictures, music or video files, launches an appropriate application to play or display the content.[1] If available, settings in an autorun.inf file can add to the options presented to the user.

AutoPlay is based on a set of handler applications registered with the AutoPlay system. Each media type (Pictures, Music, Video) can have a set of registered handlers which can deal with playing or display that type of media.

The AutoRun sequence starts with the initial discovery of a new device or new piece of media. Following this, notification of interested parties occurs, of which the Windows Explorer shell is of primary interest. After checking certain Registry settings to see if AutoRun can proceed, parsing of an optional autorun.inf may occur and any necessary actions are taken.

The initial sequence is handled much the same in every version of Windows from Windows 95. However, the way the autorun.inf file is read and acted upon and the level of integration of AutoRun with AutoPlay has changed significantly from the time AutoPlay was introduced in Windows XP until the present handling in Windows 7. In Windows 10, Microsoft has added the option to enable autorun in its settings. Not only users can turn it on but also they can choose specific external devices for autoplay.

When a device with AutoRun-compatible drivers receives new media, a "Media Change Notification" event occurs. The Windows OS then notifies interested applications that a device change has occurred. The notification method used can change depending on the device type.

If the device changed is a volume (like a CD) or a port (like a serial port) Windows broadcasts a WM_DEVICECHANGE notification to all top-level windows.[2][3] Windows calls this a "basic" notification. A top-level window is one which is a descendant of the desktop.

Non-volume devices are those devices that do not appear as drive letters in "My Computer". These are not handled by any part of AutoRun - any actions taken for these devices are taken either by device specific software or by AutoPlay. See AutoPlay#Devices that are not drives.

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.[9] This includes DRIVE_REMOVABLE, DRIVE_FIXED and DRIVE_REMOTE drive types.

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.

With the introduction of AutoPlay in Windows XP, the final stage action (stage 7 above) for some drive types changed from executing an application to invoking AutoPlay. From Windows Vista, the AutoPlay system is integrated into every aspect of media handling and there is no automatic execution of the AutoRun task.

The default Registry settings add Removable drives to those that initiated AutoRun. In Windows XP and higher, except Windows Server 2003, only the Unknown and Remote drive types are not active for AutoRun.

The handling of the autorun.inf file changes very significantly between each Windows version. The details can be found in the autorun.inf article. The current handling in Windows 7 is that only drives of type DRIVE_CDROM may specify an AutoRun task, alter double-click behaviour or change context menus.

AutoRun consults Windows Registry values to decide whether to initiate actions for any particular drive or drive type. These values can be changed using several methods, one of which is using Group Policy.

The primary relevant Registry entry names are NoDriveTypeAutoRun and NoDriveAutoRun. These exist in both per-machine and per-user settings and their location and priority in the Registry are described in further detail below.

A Registry value consists of a name-data pair. Microsoft documentation commonly uses the term "entry" as an equivalent term. It also uses "value" for "data" when it is obvious what is meant. To avoid confusion, this article always uses the term "entry" when referring to the name-data pair.

Two Registry keys that are very commonly referred to are HKEY_LOCAL_MACHINE which contains per-machine settings, and HKEY_CURRENT_USER which contains settings for the currently logged-on user. These are almost always abbreviated as HKLM and HKCU respectively. There may be many users of a machine; their settings are stored in HKEY_USERS, HKCU is actually just a link to the appropriate place in HKEY_USERS.

Registry settings may be changed directly by using the GUI regedit tool or the command line reg.exe utility. Settings can also be placed in a text file,[11] named with a .reg extension type. For example, "mychanges.reg". When the file is double clicked, the settings in the file are entered into the Registry, permissions allowing.

The NoDriveAutoRun and NoDriveTypeAutoRun Registry entries can exist in two places, the per-user setting (under HKEY_CURRENT_USER) and the per-machine setting (under HKEY_LOCAL_MACHINE). If an entry appears under HKEY_LOCAL_MACHINE, then any corresponding entry under HKEY_CURRENT_USER is completely ignored. The data values are not merged in any way.

When deciding whether to activate AutoRun, both NoDriveAutoRun and NoDriveTypeAutoRun Registry entries are consulted. If either value indicates a drive should be disabled then AutoRun is disabled for that drive.

the data value taken for NoDriveAutoRun is 0x08, disabling drive D and the data value taken for NoDriveTypeAutoRun is 0x95, disabling removable and network drives. The per-user NoDriveAutoRun entry is never used.

This Registry entry disables or enables the AutoRun feature on all drives of the type specified.[12] It reflects the setting of the relevant Autoplay Group Policy. Valid data ranges from 0x00 to 0xFF in hexadecimal notation. If the entry is not present, the default data value is either 0x95 or 0x91 depending on the version of Windows used. An entry present in HKLM overrides any entry present in HKCU.

Note that bit number 1 is unused and that the "Unknown" type is represented twice. Setting all bits to 1 would give a hexadecimal value of 0xFF, decimal 255, and would disable AutoRun on all types of drives.

This Registry entry disables or enables the AutoRun feature on individual drives.[14] It is not associated with a Group Policy and does not exist by default. The data value is taken to be 0 if the entry is not present. An entry present in HKLM overrides any entry present in HKCU.

The data is a 32 bit (DWORD) bitmapped value, of which the lower 26 bits are used to represent each of the 26 drive letters from A to Z. Thus the valid data range is from 0x0 to 0x03FFFFFF. The least significant bit (the right most bit) represents drive A, and the 26th bit from the right represents drive Z.

The only Group Policy settings available for AutoRun affect the NoDriveTypeAutoRun Registry entries. The policy is available on either a per-machine or a per-user basis reflecting the Registry entry location in either HKLM or HKCU.[12][14] As described above, a per-machine policy setting will cause the per-user policy setting to be ignored.

When a policy is Enabled, Group Policy will add the NoDriveTypeAutoRun entry to the Registry. If the policy is Disabled or set to Not configured, Group Policy deletes this entry from the Registry for the Machine policy (in HKLM) and sets it back to system defaults value for the User policy (in HKCU). System defaults may then take effect as described in the NoDriveTypeAutoRun section.

The policy names, locations and possible settings vary slightly between Windows versions. The list of settings are relatively short and are always additional to the system default setting. Therefore, on Windows 2000, enabling the "Disable Autoplay" policy and setting it to "CD-ROM drives", disables AutoRun (as distinct from AutoPlay) for CD-ROM and DVD drives, removable drives, network drives, and drives of unknown type.

This setting cannot be used to enable AutoRun on drives on which it is disabled by default or disable AutoRun for drives not listed. To disable or enable any particular drives or drive types, the Registry must be edited manually.

In these versions of Windows, the ability of an autorun.inf file to set an AutoRun task, alter double-click behaviour or change context menus is restricted to drives of type DRIVE_CDROM. There are no policy settings that will override this behaviour. Policy locations and settings are as per Windows Vista, Windows Server 2008 above with the addition of:[16]

c80f0f1006