I went through and cleaned up my Serum User presents folder, which involved renaming a bunch of subfolders that I had in there. From within Serum, I selected "Rescan folders on disk" but the older folders remain in my presets panel, meaning Serum can't find any of the presets in the new locations. I've tried removing and reinstalling Serum to no avail. Is there some sort of cache that needs manual clearing? Am I misunderstanding the behavior of "Rescan folders on disk"?
UPDATE: Figured out if I delete all the presets, then rescan, then restore the presets, then rescan again, it resolved the issue.