Notification for downloading ( flashing down arrow) on status bar gone

[zhong]

Recently I clicked cleared notification status bar at the top of tablet.

Now when I download using 4 Shared sync app. there is no down arrow flashing at the top left status bar notification when I click on th file to start downloading from 4 shared sync app. and notify me successfully download at the end doesn't notify when done.
Is there something I have to enable to get that back ? I am use Curtis LT7029 tablet Android 2.3 O.S..

Thanks.