Source New mail envelope and Windows 7
Outlook 2010
When you are using Outlook 2010 on Windows 7, then the new mail envelope will no longer be displayed in the Notification Area.
Instead, the icon of Outlook on the Taskbar will actually change to
inform you about a new message.
Unfortunately, when you’ve set your Taskbar in Windows 7 to use small
icons, you will not get an envelope notification at all.
In that case you could consider reconfiguring the New Mail Desktop
Alert to be displayed as a permanent notification.
Note 1:
The new mail envelope is only being displayed for messages delivered
to the (default) Inbox. For additional accounts you can use a New Mail
Desktop Alert.
Note 2:
The option to show/hide the new mail envelope for Outlook can be found
in;
Outlook 2007 and previous
Tools-> Options…-> tab Preferences-> button E-mail Options…-> button Advanced E-mail Options…-> option: Show an envelope in the
notification area
Outlook 2010
File-> section Options-> section Mail-> option group Message arrival-> option: Show an envelope in the taskbar
