Okay, first off, I'm not very knowledgeable about computers. I'm a gamer, but ya...thats about it. So, I got a blank CD-RW(from Sony), and saved some stuff on it for a school project. The project is over, and now I want to use it for other things. But its sais its read only, which I never said for it to do. How do I change it to writable again?