Lost music

my husband has changed the name of some music in the
media library that was previously "unknown". Now the
music will not play and the files are missing from the my
music folder. I've already searched the C drive for it
and the entire windows media player finds it, but it
won't play becuase it has been "renamed or deleted". Yes
it was renamed but not deleted. How do I recover the
files? Is it possible for the player to be able to delete
the files itself?

Sincerely frustrated,
Becky