Outlooks 2016 New Mail Icon With Yellow Envelope is Missing In Taskbar

Sometime in the last week or two I noticed Outlook's little yellow indicator for new email is missing in the taskbar.
When a new email arrives, Outlook plays a sound but does not display the yellow envelope. It will also display a Desktop Alert if asked to do so. I don't ask.

Here is what I have done:

1. Right clicked the taskbar and chose settings/notification/select which icons appear on the taskbar/Microsoft Outlook you have new unread email messages. That is ON.

2. In Outlook, chose File/Options/Mail/Message Arrival checked Play a Sound and also Show an envelope in the taskbar.

Windows 10 version is 1607 Build Number 1607 14393.693
Office 2016 version is 1611 7571.2100.

I will really appreciate any help here.

Thank you.

Whoops! I knew I left something out.

I have also run sfc /scannow and it reported no problems.

Interesting. My envelope has always turned yellow whenever new mail arrived. Now when new mail comes nothing changes.

It has been my practice to be able to just pass by my computer and with a glance to see if the little box is yellow telling me I nave a new email. It has been that way for years at least back to W7 and maybe XP and I would like to continue that. Had no problem with it in Windows 10 until a few days ago.

That's one of the annoyances of W10. Sometimes icons, always on the rightside, disappear from the taskbar. Today e.g. the icon of Malwarebytes disappeared. Restart is needed to bring it back.

Thanks but the Outlook icon is over near the left side. Go figure!

Very strange indeed