In order to leave the Single User Mode, type ‘reboot’.

Note: In case you receive any other message like ‘File system was modified’, then you should keep running the fsck –fy message until ‘The volume (name) appears to be OK’ message appears.

A message stating ‘The volume (name) appears to be OK’ appears after the repair process is complete.

Type fsck –fy command after the # sign.

This is a command prompt where you need to type the command.

A small box appears at the bottom of the screen.

This ensures that you have logged in as a Single User Mode.

You will see some white text on black background.

Note: You can successfully do this, if you hold down the Command+S key as soon as you hear the boot chime.

Hold down the Command+S key to boot Mac into a single user mode.

For this, you need to follow the below mentioned steps. In order to repair a disk using an fsck command, you need to log in into the Mac using a single user mode. It can easily run on the command line to perform an HFS disk repair for Mac. Generally, the command runs automatically at the boot time, but, the command can also be manually run in case there is any problem with the file system. However, there are various fsck tools, which can be used to repair the damaged file system.

Primarily, the fsck command is used to check the consistency of the file system.

Fsck is a very simple command supported by UNIX and UNIX-like operating system including Mac OS X. Mac supports various tools including the file system check ‘fsck’ to repair a corrupt Mac Disk. A user can make use of the command line option to run various commands. There are other options as well, which a user might try. Such a situation remains very challenging for the user, as he would not be able to repair his corrupt Mac disk. One of the most simple and easy ways is to go to the Recovery mode and use the disk utility option.īut, there are times when the disk utility might not work or such an option might not be present at all. It is an extended format of the HFS file format, which was used in earlier Mac computers and iPod music players. Note: Mac uses an HFS+ file system for their hard drives. However, there are various options available on the Mac platform to repair the disk. There are various reasons that can cause corruption in a hard disk. Mac, which is shipped with one of the finest hard drives, also stands a risk of getting corrupt. In spite of the latest technology used in the majority of the hard disks, they are always prone to corruption.

Mac os disk utility man page