View Full Version : How to reinstall OS X and backup data?

Jan 19, 2011, 05:44 AM
Iīm having hard times with my MBAir (old model, only one usb port). If you could help Iīd appreciate it. Thanks in advance!

Symptoms: The MBA doesnīt turn on. When I push the power button, the led light appears, the screen goes grey with the apple (as normal) and after 8-10 seconds, puff... it goes off.

Diagnosis (via Macīs Genius Bar): The hardware is fine, the data is there, the OS X is corrupt

How to fix it: Reinstall the OS X

My main problem: I need to do the backup of the data (very important) and reinstalling the OS X deletes the internal HD completely

So, what Iīve been told:
1. Install the OS X on an external HD;
2. Power on the MBA, running the OS from the external HD;
3. Save the data;
4. Reinstall the OS X in the MBA

Seems easy, but itīs not:
Question 1. How do I install the OS X on an extHD, having 2 separate CDs, from a PC?
Question 2. Does it (the extHD) needs to be formatted?

Any further tips are extremely valuable! Thanks**

Jan 19, 2011, 05:53 AM
Not easy but Genius should have told you this.

Do you have external CD/DVD drive that you can boot from?

hold down the alt/option key on the keyboard as soon as press the power button. A boot selector screen should come up giving you choice to boot off from.

Insert your Mac OS X DVD and it should appear in the boot selector screen boot selector screen. Select your DVD and it should boot off from your mac OS DVD.

You should be able to rest. but this should get you started.