Probable cause: Title text frames were deleted and replaced with text "box."
Cure: Use PowerPoint's templates as they are delivered.
PowerTOC ignores slides that don't have what it considers a "title." If you enter text outside of the appropriate text frame, it will be ignored. For example, if you delete a frame that says "Click to add title, " PowerTOC won't find any titles and, therefore, can't put add them to the table of contents.
Regardless of the slide type, click in the title and subtitle text frames to enter the text you want included in the table of contents.
Figure: Title slide
Figure: Normal slide