This hit me over the years so I tossed WMP for other players.
I have a particular problem with media files not appearing in the WMP library. The usual fixes work for a week or two, then it fails again. I have a W7 64-bit PC that is always kept in a fast, healthy condition. Every few weeks, I find that new media files do not get picked up by WMP, even though a similar operation worked a week before. This has been going on for more than a year. I can rebuild the database, as always recommended for a corrupted database. But this fixes it only for a week or two, then it happens again. So I have done the more aggressive regular suggestions, including uninstalling and reinstalling WMP. But this only lasts a week or so too. Often the failure appears in a very odd way: in Explorer, I add a few MP3, JPG or video files and delete a few. When I open WMP, it updates but the discarded files do not disappear and some but not all the new files will appear. I re-start everything to see if it resolves, but it gets worse. The new files which were picked up disappear, and the WMP database still displays the old, discarded files. Any ideas? I am reluctant to reinstall Windows from scratch for such an irritating but marginal problem.