Why does my Tray Icon's Behavior occasionally reset Windows 7?

Solution 1:

You might be interested in this Microsoft support article, "FIX: The Taskbar is reset to the default settings when you use the "Automatically Log On" feature in Windows 7 and in Windows Server 2008 R2" (KB979155).

It seems that the notification area settings in the registry are overwritten due to a race condition between explorer.exe and taskhost.exe.

Solution 2:

In Outlook 2007 and 2010, the envelope will show for messages that are delivered to the default Inbox for each account. When a message is caught by the Junk E-mail filter or moved by a rule, the envelope icon is not shown. The icon is also not shown for additional mailboxes which have been configured from a single Exchange account.

Ensure also that in Outlook 2010 that you have chosen File-> Options-> section Mail-> option group: Message arrival-> option: Show an envelope icon in the taskbar.

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If your case is not one of the above, then read this from New mail envelope and Windows 7 :

If you are using Outlook 2010, then the new mail envelope is not being displayed in the Notification Area (also knows as the Systray) but on the Outlook Taskbar icon instead.

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.

It may seem that your taskbar preferences conflict with the way Microsoft wants you to use Outlook, so you may have to adapt to it, or use another mail client.