I put MS Word & Excel docs on a CD-RW. Now I can only "read" and can't make changes. If I move the docs somewhere else to make changes, I cannot move it back to that CD because it says it is a read only.In snooping around in "properties" I see a message that it can be formatted, but I don't know how..... So for future use, is there something I should have done before using that CD to format it? (I'm kind of a newbee on these subjects).............thanks.