Basecamp cant' find recently installed maps.

I recently installed City Navigator NA NT 2021.10 to my Nuvi device.  I selected install to computer also - D:\ProgramData\Garmin\Maps.  The data seems to be present in the selected folder, but Basecamp does not list it as a possible map to select from the Maps pull down.  What else do I have to do have Basecamp use 2021.10?