Mark has a huge hard drive with over 300,000 songs and videos. Is there any software that can go through the list and remove any corrupted or damaged files automatically? Leo says that Media Monkey has some great tagging and music management features. It's free to try. Mark could have it reorganize his folders, but if there's a corrupted file, there's no real way to know it unless he plays it.
The chatroom also advises backing up the music before he messes around with it, just in case tragedy strikes. Another option is a program called Mixed In Key.