If you use Windows XP or below, right click on the system tray, select Properties and press the Customize button. Go to HP Image Zone and select Always show from the drop-down list below the Behaviors tab.
If you use Windows Vista or above, go to Start > Control Panel > Appearance and Personalization > Taskbar and Start Menu and click Customize from the Notification Area field. Go to the HP Image Zone application and select Show icon and notifications option from the drop-down list below the Behaviors tab.