My near 3 month old samsung 1tb external hard drive has just packed in. Whenever I plug it in it comes up with a message reading OS X can't repaid the disk "Samsung" You can still open or copy files on the disk, but you can’t save changes to files on the disk. Back up the disk and reformat it as soon as you can. It worked fine this morning and now it will not work at all. Anyway I have gone into disk utility and I have clicked erase and it will not allow me to do this either. Basically I need to format my external hard drive as quickly as I can so that I can re back up all of my work - but it will not let me. Do you have any tips? Please help Thanks!!