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Same problem here please help!

I'm getting this too. Extremely frustrating.

App Store support. There is troubleshooting and a contact link.

Support

I had a similar issue on a used macbook air that I purchased and was attempting to reinstall the OS X from the partition. The issue was the partition was referencing a BETA version of yosemite that could not be downloaded any longer. You may have the same issue. The solution is an internet recovery process. You start the mac and then immediately press command+option+R at the same time. This should take you to a screen with a spinning globe and it will start this internet recovery process. My understanding is it downloads the original partition recovery file for your specific machine. In my instance it downloaded mountain lion. Once this is complete I went to disk utilities and first re-erased the Mac SSD and then performed the OS X re-install from the recovery partition. It will not ask for any sign in with your apple ID. It will simply install the original OS X that came with your machine. You will then go through the setup process to establish the mac as your machine or install from backup which ever you choose. Once that is done you can do the free upgrade to the latest OS X, in my case yosemite. Hope this helps.

I was having the same problem and this worked for me. THANK YOU!

I had this issue with my iMac. What fixed it for me was using my old iTunes login credentials rather than my iCloud login credentials.

pressing right after restart Command Option R

It did worked the "option + command + R" (press when you start) method. and then I erase my HDD then went to OS X Yosemite, after log in to any of my Apple ID, then finally it start working! thx

This is a worrisome condition!

Is there any way to fix this without having to reformat my entire Macbook Air?

Thank you so much for the tip. I was trying to reinstall my nephew's macbook air and that message kept on popping out. Your tip save my time. Thanks