Hello,
Sorry to hear you are having issues. But, do you set your Windows system notifications to ON? When I have this turn on, I do get popup notification when new msg come in.

Thank you.
Basj,
Stardock Community Assistant.

Thank you for your reply.

For basj: Yes, I do have system notifications turned ON.

For Neil, I believe I have the taskbar hidden by using the Start11 taskbar setting to hide the taskbar.  If I right-click on the taskbar and select 'Taskbar settings,' I get to Settings>Personalization>Taskbar, and in those settings the option to 'Automatically hide the taskbar' is NOT checked.  If I recall, when configuring Start11, it said that I should disable the system setting to hide the taskbar and enable the Start11 option.

Yes, there is a notification of new IMs in Teams on the taskbar.  It is just that the taskbar does not appear and flash as it did with Windows 10 (without Start11 installed).  Due to significant deficiencies and taskbar changes in Windows 11, immediately after upgrading to Windows 11, I began looking for options to enhance the native Windows 11 taskbar abilities (namely, moving the taskbar from the bottom to the top).  That is how I found Start11.  I immediately installed Start11 after upgrading to Windows 11, so I did not take any time to learn the subtle differences between Windows 10 and Windows 11.

Thank you for your time.  I guess this is just an issue I'm going to need to learn to deal with.