The Notifications Settings window:
You can set three forms of notifications, Popup window, notification icon in tray and sound.
Notification icon in the tray area is discrete and the lest intrusive, suitable for less important events.
Show popup windows will display a popup window containing all the relevant information about the event.
Play sound, you can specify a different sound file to be played for each type of event.
There are five types of events you can set notifications for:
Incoming mail
IM message received
Incoming file transfer
IM status change
and Reminder for Events and Tasks
You may choose a combination of notifications for each event according to their level of importance to you.