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Nothing has changed in notes section. It is pretty much same as it was in older version.If it doesn't work for you then you may try to reset the preference of PowerPoint by renaming the file.
Make sure PowerPoint is closed. Then navigate to the path mentioned below:
Substutitute <UserName> with the user name set for your computer.
The table below shows PCB file names that correspond to each PowerPoint version:
Version PCB file name
PowerPoint 2007 PPT12.pcb
PowerPoint 2010 PPT14.pcb
PowerPoint 2013 PPT15.pcb
Within this folder, you will find one or more PCB files,Now you can either delete the PCB file or you can rename it with a .bak or another extension.Either way, if PowerPoint cannot find a PCB file while loading, it will generate a new PCB file thus rolling back all PowerPoint's customizations to an earlier stage.
Note :- Renaming the .PCB file will reset your customization of PowerPoint.
Please let me know if that works.
Thank you so much for your reply and your suggestion. I did access the directory you mentioned and renamed the .PCB file. I republished one of my projects and am still not getting the PPT slide notes to appear in the Notes tab of the Presenter player. Interesting though, after making the changes and publishing, I returned to the directory you mentioned to see if a new .PCB file was generated, but to my surprise, I found that one did not get created. Interesting, but not helpful to my current issue. :-(
Thank you again for your help. Please let me know if you think of anything else I may be missing. This is very odd.