Hello,Please disregard my last message, it was intended for another customer.I will open your question to other experts now.No need to reply.Regards,
Hi there! My name is*****'m a certified computer professional with 15 years of experience. I'm terribly sorry that this happened to you. Can you tell what the model of the MacBook Air is? Or a serial number so I can maybe figure it out? Also, do you know what version of MAC OSX is running on it? If I know that I can provide instructions for reinstalling the operating system. This does mean that you will loose files and documents though. Do you happen to have a backup of anything important on the drive?
I apologize for the delay. For some reason I wasn't notified of your response. If you don't have anything on the computer that you need to preserve you should be able to do a clean install of Mountain Lion using the following steps.
Here’s how to install (or reinstall) OS X, step by step:
Boot from your Recovery HD partition by restarting your Mac while holding down the cmd+R keys.
The OS X Utilities window appears. Select Reinstall OS X, and click Continue. The OS X Mountain Lion splash screen appears. Click Continue.
A notice will appear telling you that your computer’s eligibility needs to be verified by Apple. Click Continue to begin the process of installing or reinstalling OS X.
If you’re not connected to the Internet, you’ll be asked to choose a Wi-Fi network from the AirPort menu in the top-right corner.
The Mountain Lion software license agreement screen appears. Read it and click Agree.
Click agree again when asked to confirm that you clicked the Agree button.
Choose the disk on which you want to reinstall OS X by clicking its icon once in the pane where you select a disk.
If only one suitable disk is available you won’t have to choose; it will be selected for you automatically.
Click the Install button.
If you have any questions or concerns during the process or need any clarification, please let me know.
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