I have an Airport Extreme that is a few years old. For years now, I have had a 500GB USB drive (2 partitions) connected to the Airport Extreme for Time Machine backup, and it has worked. Recently, the Airport Extreme has been reporting that the "Disk Needs Repair", and Time Machine backups have been failing. I have erased and reformatted the disk (always as a Mac OSX Extended file system), and verified/repaired. Disk Utility never finds any errors. I have tried a new disk (same formatting). I have tried a new SATA-USB connector. Same "Disk Needs Repair" error from the Airport Extreme in all cases. I have googled, but found no specific answer. Some say to reset the router (done, no help), some say to update firmware (it's been updated), some say Does anyone have any ideas?