When you update a program in Windows 7 or in Windows Server 2008 R2, the corresponding program icon in the notification area is lost or moved to the hidden overflow area.
This issue is fixed in the January 2010 stability and reliability update for Windows 7 and Windows Server 2008 R2 (KB 977074).
To resolve the issue, install update 977074. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
977074 The January 2010 stability and reliability update for Windows 7 and Windows Server 2008 R2 is available
To work around this problem, you can manually promote the icon back to the notification area. To do this, follow these steps:
Click the Show hidden icons arrow in the notification area, and then click Customize.
Click the drop-down list that is next to the icon that you want, click Show icon and notifications, and then click OK.
For more information about the Action Center feature in Windows 7, visit the following Microsoft Web site:
http://windows.microsoft.com/en-GB/windows7/products/features/action-centerFor more information about the notification area in Windows Vista, visit the following Microsoft Web site:
http://windows.microsoft.com/en-US/windows-vista/Show-or-hide-the-notification-area-system-trayFor more information about the Shell_NotifyIcon function, visit the following Microsoft website: