I have Outlook minimize to tray. I set the "Microsoft Outlook" icon to "Show icon and notification" in the Notification Area Icons settings (this is the main Outlook "O" icon). That one works fine. I also have the "Microsoft Outlook (You have new unread email messages.)" icon set to "Show icon and notification" (this is the envelope icon). That one works for a while, but then it gets hidden. When I go back into the Notification Area Icons settings, it still shows up as "Show icon and notification" but there is another one in the list that has the same envelope icon and shows some weird file name, currently it's "339e3812.rbf (You have new unread email messages.)" and it is set to "Only show notifications". If I change it to "Show icon and notification" it comes back, but then after a while it will change to a different file name and disappear again. Why does it do this? Is there any way to make the envelope icon always appear when there is new mail?

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I have Outlook minimize to tray. I set the "Microsoft Outlook" icon to "Show icon and notification" in the Notification Area Icons settings (this is the main Outlook "O" icon). That one works fine. 

I also have the "Microsoft Outlook (You have new unread email messages.)" icon set to "Show icon and notification" (this is the envelope icon). That one works for a while, but then it gets hidden. When I go back into the Notification Area Icons settings, it still shows up as "Show icon and notification" but there is another one in the list that has the same envelope icon and shows some weird file name, currently it's 339e3812.rbf (You have new unread email messages.) and it is set to "Only show notifications". 

If I change it to "Show icon and notification" it comes back, but then after a while it will change to a different file name and disappear again. Why does it do this? Is there any way to make the envelope icon always appear when there is new mail?