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my macbook air will not not boot up.

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my macbook air will not not boot up.
Hello and thank you for asking your question, with
I am Sr. Mac Tech Support Specialist, Terry, glad to assist you.

**Please note: An "Answer" by me, or an"Accept" from you, does not mean the session has ended. So please remain patient with me and I will work
diligently, to resolve your technical question to your satisfaction.-Thanks!*
Here are some steps you can try to resolve the issue:
• First, check that the MagSafe adapter is properly seated in the MagSafe port on your Macbook Air. Make sure to also check the MagSafe connector on the adapter for any bent or damaged pins, debris, or alignment issues with the connector.

• Check the MagSafe connector port on the Macbook Air for any damaged pins or even wear and tear (meaning exposed or severly bent cables, etc) on the cable.

If your adapter appears to be in tact and without any noticeable damage, then proceed to perform a SMC Reset procedure for your Macbook Air:

The System Management Controller is an integrated circuit (computer chip) that is usually on the logic board of your Mac portable.

It is responsible for power management of the computer. It controls backlighting, hard disk spin down, sleep and wake, some charging aspects, trackpad control, and some input/output as it relates to the computer sleeping.

Shut down the Macbook Air.
• Plug the MagSafe power adapter into a power source connecting to your Macbook Air if it is not already connected.
• On the keyboard, (left side) press Shift + Control + Option keys and the Power button at the same time.
• Release all the keys and the power button at the same time.
• Now turn on the Macbook Air by just pressing the Power button
(Quick note: THe LED on the MagSafe power adapter may change states or even temporarily turn off when you perform an action like an SMC reset)

Let me know if this helps.

This is my first answer, but certainly not my last, as long as this issue remains unresolved.

Please do not press "Accept" until you have experienced a resolution from this answer and are satisfied with the results.

If you have not achieved the desired resolution with this answer for any reason, please update me as necessary, with details of what you experienced.

This will allow me to continue working to resolve this technical issue for you.

I will be watching for your next reply.



Customer: replied 6 years ago.

The power adaptor seems in good condition. The problem persists regardless of whether the power supply is connected or not.

I pressed the shift+control+option+power key and the power lead connector birefly turned from orange to green. I then released all keys at the same time. I then pressed the power key and it powered up. The same problem occures:


It powers up, the screen goes white with the apple logo, the whirling timer icon spins away for about 2 mins then it shuts down. I was working perfectly prior to when I last shut it down...

Thanks for your detailed update.

Two things I would like you to try:

Option I
If your Macbook Air's battery is fully charged, try repeating that same process as I provided to you earlier. If you are able to get more functionality from your Macbook Air on the battery power alone, then the issue is with your MagSafe adapter and you will need to consider replacing that cable as it is more than likely defective.

Option II
Now if you try on battery power alone with the same result, of the Macbook Air shutting down after just a few minutes of activity, I would like you to get your Mac OS X installation disk and try booting up to the install disk using the procedure I have provided below, but do so with the MagSafe power adapter connected.


Insert your Mac OS X Startup disk
•Reboot your Mac
•At the Apple Chime, press the C key and hold it until you see a White screen, gray Apple and eventually a Spinning gear.
• Release the C key only after you see the Spinning gear.
•Mac will boot from the startup disk to the Installer environment
• From the Installer Menu bar, click Utilities > Disk Utility and open up Disk Utility application.
• Click on on the hard drive at the top of the window in the left sidebar and
• Select "Repair Disk"
**Let Disk Utility run this repair the disk until completion
• At the end of this process, reboot your Macbook Air

Let's see if this helps.

Thanks again for your patience, I will be awaiting your next update.


Customer: replied 6 years ago.

Hi Terry


The problem first occured while the power lead was connected. It is generally always connected so the power is generally full or close to it.


In regard to Option 1: I have now tried the shift+control+option+power reset with both the power connected and disconnected. The result is the same; when the power key is then subsequently pressed the machine does the same thing.


In regard to Option 2: Terry, you sound like you know your stuff and are quite expert. Now it's my turn to reveal my skills... I do not have the start up disk and do not know where it is. I hope it is in the office but I will have to have a good root around. I know they are important but I never think I will need them. So, I am the dummy in this deal.


I have the machelp order number.If I can find the disk then I will log back on and get further help along the lines you suggest.


If I cannot find the start up disk, what are my options? (Apart from buying new macbook pro and keeping the disk that comes with that!!)


Please advise, and accept my apologies for being beyond help!


Kind Regards.... Iain

"So, I am the dummy in this deal."

I don't think so Iain-- After all you used enough wisdom to come to us for help right?

So you are A-ok from our side because you have come to seek help from those who do know how to help you resolve such issues like this for your Mac. So I have to say on the behalf of JustAnswer and myself as a Mac tech, thanks for making a smart move and contacting us!

And there are still options to help you.
What I would like you to do, with the MagSafe adapter connected, if you can, is to try this process outside of using the Mac OS X boot disk:

Start up your computer in Single-User Mode to reach the command line by doing this:
•Make sure your Mac is shutdown.
• Reboot your Mac
• When Mac starts up, press the Apple Command key+ S Key
- A black screen, with white text appears
• At the command-line prompt, type: /sbin/fsck -fy
• Press Return.

--fsck will run through a series of tests and will return information about your disk's use and fragmentation. When completed, it will display this message if no issue is found:

The volume (name_of_Mac_volume) appears to be OK

If fsck found issues and has altered, repaired, or fixed anything, it will display this message: --FILE SYSTEM WAS MODIFIED--

Important: If this message appears, repeat the fsck command you typed at the beginning, until fsck tells you that your volume appears to be OK (first-pass repairs may uncover additional issues, so this is a normal thing to do).

• When fsck reports that your volume is OK, type reboot at the prompt and then press Return.
• This last command after completing the fsck process, is going to attempt to boot your Macbook Air to the main desktop.

So try this and let me know if this helps.

Customer: replied 6 years ago.

Things have happened, but it dont look good.


Below is an exact copy of what now appears on the mac screen following the command: /sbin/fsck -fy


** /dev/rdisk0s2

** root file system

** checking journaled HFS Plus volume

** checking events overflow file

** checking catalogue file

disk0s2: I/Oerror.

Invalid sibling link

(4, 37711)

** Rebuilding catalogue B-tree

** The volume Macintosh HD could not be repaired

/dev/rdiskos2 (hfs) EXITED WITHOUT SIGNAL

:/ root#


SORRY TO BE LONGWINDED, but thought this all might be important.


I have left it as is, just staring at me all angry ;o)


Cheers Terry...

No problem Iain.

I appreciate you actually taking the initiative to provide me with the error thread from the fsck error.
It helped more than you know because now I know what is wrong.

The reason your MacBook Air was not staying on but for a few mins before shutting off, is due to the Mac OS X directory located within the Mac OS X volume on the hard drive has failed. Your hard drive is fine, but your current version of Mac OS X is going to have to be either repaired or erased and re-installed.

There is an excellent diagnostics and repair software for Mac that is one of the best (in my opinion) utility softwares for Macs on the market today. If you do not want to erase and reinstall your Mac OS X software, then
DiskWarrior 4.3 is what you will need. In your previous reply, within the error thread there was the clue to the issue you were having:
"** Rebuilding catalogue B-tree
** The volume Macintosh HD could not be repaired
/dev/rdiskos2 (hfs) EXITED WITHOUT SIGNAL"

This is an indication that the Catalog B Tree within the Mac OS X volume is damaged or corrupted and cannot be repaired, which is what is needed fir you to boot your MacBook Air normally. Disk Warrior takes on correcting this type of error by rebuilding the damaged Catalog B Tree index file and recreating a brand new Mac OS X directory.

This software runs for under $100 USD but is worth the investment to correct this issue.
The link to the developer's website is

This Iain, would be the fix that you need to fix this problem-- Otherwise you are looking at having to perform an Erase and install procedure with your Mac OS X install disk when you have access to that disk, if that is the path you wish to take.

Let me know if you have more questions regarding this information Iain, as I am here to assist as well as I can.
But I take no hesitant moves here when I say this is my most viable answer for you.



MacTechTrainer and 2 other Mac Specialists are ready to help you
Customer: replied 6 years ago.
hi terry, are you there?