Taskbar notification area overview (Help and Support).
The notification area of the taskbar is where you usually see the current time displayed. This area can become crowded with notification icons that appear when certain events occur, such as when you receive e-mail or when you open Task Manager. Windows displays a notification icon when an event occurs. After a short time, Windows puts the icon in the background to simplify that area.
You can access the icons that have been placed in the background by clicking a button in the notification area.
In addition, you can customize the behavior of notification icons on the Taskbar tab of the Taskbar and Start Menu Properties dialog box.
To open the Taskbar and Start Menu Properties dialog box, right-click an empty area on the taskbar, and then click Properties.
For more information, click Related Topics (Help and Support).
283084 - How to Clear Past Items from the Notification Area
279771 - Description of Notification Area Settings
321213 - Icons in the Notification Area May Disappear If You Use High-Contrast Color Themes
As you are aware many programs have property pages (often obtained via a right click on an icon) that allows removal of the icon from Taskbar Notification Area.