Hi i am writing this on behalf of a friend who has recently purchased a MBP. he has noticed that the superdrive refuses to read discs that have been burnt on another machine. it reads original company discs happily but when a burnt disc is inserted the MBP believes that the disc is blank and then asks what to do. The discs have also been checked in other machines and function correctly. it also cannot burn discs. The only possibility that i could think of was to reinstall OSX however this would involve quite a large amount of reinstallation. Can anyone think of an alternative explanation/solution?