Every time I do a manual import, I get notified of a number of skipped files which were "previously determined to be bad". I took care of these bad files a long time ago (they were all .m4p files which I converted to .m4a). Those "bad" files do not exist anywhere anymore. But MC still complains about them. One recommendation I found involves creating a smartlist via "[Media Type]=[Audio] ~d=b", and operating on the results. That doesn't work because those files no longer exist, and that smartlist comes up empty. I tried various flavors of "Fix Broken Links" (Yes, Yes with protect files on missing drives). No effect.
What is the recommended procedure these days for handling this situation? I just want MC to forget all about these files. Running MC21 on a MacPro, Mac OS 10.11.5.