When I try to organize and consolidate my libary, I get a message saying that I do not have the priviledge to change files.

I am trying to move my itunes library from my macbook air to a new windows 8 computer. I changed the location for the media file, then tried to organize and consolidate the itune library files. I got a message that I do not have the priviledge to change the files. How do I resolve that?