My Mac is acting weird

Having trouble starting up your Mac? Are you staring at your screen waiting for the Apple logo with the spinning gear to come up? it taking forever?

..then you see the dreaded flashing question mark or the circle slash icon…This means your Mac cannot find your startup disk and you could be looking at a corrupted file system or a failing hard drive. Here are the options you have to perform basic troubleshooting with your Mac:

  • Start up your Mac using your Mac OS install disk and perform repairs in Disk Utility.
  • Start up your Mac in OS X recovery, which allows you to repair your disk with Disk Utility.
  • Start up your Mac in target disk mode to allow your computer to be used as an external device to another Mac via Thunderbolt or Firewire on older Macs. This will enable you to use Disk Utility and perform repairs on your sick Mac.

What if you don’t have your Mac OS Install disk…..your Recovery HD is missing…no Thunderbolt cable…you don’t have any other Mac around ?

There is still hope.

As we all know, OS X can trace its roots to UNIX and behind that awesome User Interface is UNIX. Being UNIX like you can start up in single user mode…

Single user mode allows you to start your Mac directly to console as super user, which allows you to run commands like fsck or file system consistency check and interactive repair…sounds hardcore?

All you need to know are how to start up you Mac in single user mode, what command line utility to run, and your Typing skills.

Shutdown your Mac. Press the power button and immediately press and hold the Command and s keys.

Command S

Then you will the see that big and ugly black screen with white text. The hardcore stuff…

command line utility

After it displays each step of the process, the scrolling text will stop and the last line you should see is :/ root#

At the prompt type /sbin/fsck –fy and press return.

fsck will start and once it completes, it will display this message if no issue is found:

** The volume Macintosh HD appears to be ok

If fsck finds issues or performed repairs, it will display this message:
** The volume Macintosh HD was repaired successfully

This is the message you don’t want to see:

This is the message you get if your start up volume is beyond repair and needs to be replaced. If you are lucky, you can still backup your files and hope they are not corrupted.

To exit Single user mode type reboot and your Mac will restart.

Running fsck in Single user mode is not only a great tool for troubleshooting but also for preventive maintenance to keep your start up drive healthy.

If you want to know more on how to keep your machines healthy, speak to Digistor regarding our Digistor Customer Assurance Plan, which includes “regular health checks” as part of the package.