Thank you. I thought at first that it hadn't worked, because after playing with the Sony software on the Mac, Calibre said the database was corrupted, so I'd just reformatted and copied all the books over again, which meant there were no recently read books. The title still said “recently added,” so it didn’t look any different from before. When I opened and closed a couple of books, they showed up in the list though, so it seems to be working as it should
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