Hello. One day, my MacBook Air wouldn't boot up. After booting from the Install DVD and running disk utility, it said that there was a problem with the internal hard disk drive and that it needed to be reformatted and OS X reinstalled. I am now trying to backup some of my files onto a 1TB external hard disk drive using single user mode. I have created the directory with the following command... mkdir /Volumes/lacie ...and are trying to mount the drive with the following command... /sbin/mount_hfs /dev/disk1s1 /Volumes/lacie ...however, it comes back with this message when I press return: mount_hfs: Permission denied Please can somebody help. Thanks, Nigel Garside.