How do I restore the Windows Sidebar?
Windows Sidebar no longer appears on the desktop. When you click the Windows Sidebar icon or try to run the program to start it, Windows Sidebar still does not appear. Several things might have caused this to occur. For example, Windows Sidebar may have disappeared when you uninstalled a program.
For more information on this issue, including potential causes, workarounds, and resolutions, see: Microsoft KB Article KB963010.