How to Rescan Faces Not Recognized in Older Versions of Organizer

There are many reasons why a face may not be recognized.  In my experience, each year the process gets better - but it is not perfect.  Face recognition has been around since very early versions, although it had a major uphaul around version 11.  To be honest, I don't know whether older images are rescanned for recognition to take advantage of newer and better algorithms.  That's a good question, and I'll see if I can find out the answer.  I believe that any face recognition that has already taken place will be preserved when an older catalog is converted to a newer version one.  Existing UnNamed People stacks will be transferred over to the new version for naming.

However, if you are really set on deleting all your face recognition information and starting fresh, you can do so by going to the Edit>Preferences>Media Analysis dialog and clicking on the Reset Face Analysis button.

I have never done this.  But I assume that all files that have People Name tags applied will continue to have that metadata.  The only problem will be that when you select the name in the People>Named tab, the faces will just have a generic icon until you associate the tagged name with a recognized face in an UnNamed People stack (or on the image itself in full screen view).

Rather than click the Reset button, you might want to try creating a new catalog and importing all of your files into it to see whether it looks like you will achieve the result you want after face recognition has been completed.  Make note of some folders in your current catalog where you think faces should have been found and then click on the folder in the People room to see whether the face has been recognized by your current verions of Elements.

[Edited]:  Actually, it would suffice just to import a few of the folders into the new catalog as a test of the potential result.

Please report back what you decide to do and what results you achieve.