Operating System Beta, etc. Wiki

The Windows Sidebar is a feature first seen in Windows "Longhorn" and later present in the Windows Vista and Windows 7 operating systems developed by Microsoft. The Windows Sidebar was designed to provide users with up-to-date information at a glance. The Channel Bar included with the Windows Desktop Update, the MSN Dashboard, and the later Microsoft Sideshow application can be seen as precursors to the Windows Sidebar.[1]

  • In pre reset Longhorn builds, Sidebar ran in explorer.exe, which caused massive memory leaks, thus in post reset it ran in it's own process, sidebar.exe.



A feature called Channel Bar was integrated with Internet Explorer 4 as part of the Windows Desktop Update, and was later included with the Windows 98 operating system. The Channel Bar was designed to be an information delivery system based on Microsoft's Channel Definition Format (CDF).[2] Users could subscribe to various channels—websites designed to deliver content—and receive updates from the channel provider.[3] Due to its integration with Active Desktop, information could also be displayed within Windows Explorer or in the Channel Screensaver.[4]

In the early 2000s, Microsoft Research developed an application called Sideshow to display dynamically updated information, such as news updates and weather forecasts, in a visually unobtrusive fashion on a user's desktop.[5] Sideshow would later be demonstrated during Microsoft's Professional Developers Conference of 2001.[6]

Windows Sideshow is compatible with Windows 2000, Windows ME, and Windows XP, and can be made to run on older versions of the Windows operating system. If one attempts to change the application's appearance in versions of Windows later than Windows XP, a bug causes its appearance to become completely black.

Windows "Longhorn"

The Windows Sidebar in Windows "Longhorn" displaying a contact list via a tile flyout.

The Rules and Alerts window in Windows "Longhorn" 4074.

The first version of the Windows Sidebar was included with Windows "Longhorn", first seen in Build 3683 of the operating system. This version of the Windows Sidebar used applets called Tiles to display dynamically updated content.[7] Later builds allowed the Windows Sidebar to be combined with the taskbar.[8]

In builds of Windows "Longhorn" under the 3xxx - 403x branches, the appearance of the Windows Sidebar matched the Plex visual style, and was translucent without assistance from the Desktop Composition Engine. Microsoft would later scrap the Plex visual style and replace it with one called Slate. As a result, the appearance of the Windows Sidebar was radically altered and changed to a glossy black. It could be made translucent by enabling the MILDesktop key in the Windows Registry.

Notably, Microsoft had envisioned the Windows Sidebar as a replacement for the notification system seen in previous versions of Windows.[9]

Windows Vista

After the development reset of Windows "Longhorn", the Windows Sidebar was not seen until build 5219 of the Windows Vista operating system. This version of the Windows Sidebar was not integrated with the Windows shell but hosted graphical scripts on a vertical strip.[10] The applets hosted on the Windows Sidebar were renamed as "Gadgets" with variations of individual Gadgets being included in the operating system throughout its development.

The build of Windows Vista released to manufacturing includes a total of eleven Gadgets: Calendar, Clock, Contacts, CPU Meter, Currency, Feed Headlines, Notes, Picture Puzzle, Slide show, Stocks, and Weather.

Windows 7

During development of Windows 7 the user interface for Windows Sidebar was removed, which made the desktop the sole location for Gadgets.[11] Various improvements were made to Gadgets in Windows 7.[12]

  • In early builds of Windows 7, Gadgets could not be aligned properly. In build 6956, the Gadgets applet cannot be accessed if UAC is off.
  • Some Major Gadgets are added which it's the Mod Edition named: Windows 7 Eternity Edition, the Sidebar has showed desktop gadgets.

Windows 8

Windows 8 included support for Windows Gadgets up to the Release Preview; support was discontinued in the RTM version of the operating system. According to Microsoft, this decision was made in response to potential security vulnerabilities discovered during development of Windows 8 which could allow arbitrary code to be executed while running compromised Gadgets.[13][14] Microsoft subsequently released a tool which would allow users to disable the feature in Windows Vista and Windows 7.[15]

See also

  • Windows SideShow