"Mac os x can't repair the disk You can still open or copy files on the disk, but you can't save changes to file on the disk. Back up the disk and reformat as soon as you can." I just saw this message pop up on two external drives that live in an enclosure of 4 3TB drives(12 TB in total): The 4 drives in the enclosure work independently and are not raided in any way. The 4 drives are in a startech.com enclosure connected to 2 x2.26 Ghz Quad-Core Intel Xeon Via esata cable. Luckily the drives mount okay, and I'm currently backing up the 6TB. Has anyone seen this before?