I change iMac hard disk from basic to dynamic in windows 7, after restart windows I saw that there is not any OS X for selecting by press and hold "Option" key.
I don't have any backup and the original DVD from the seller. I live in Iran and here there is no any Apple seller or supporting center.
What should I do to have OS X again ?
iMac, iOS 6.1.4, Intel i7
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You probably erased the hard drive by doing that. If you have got a Mid 2010 or later iMac, you can use Internet Recovery to reinstall OS X > http://support.apple.com/kb/HT4718 Hold Command, Option (Alt) and R keys while your computer is starting.
Then, open Disk Utility, choose your hard drive at the top of the sidebar, go to Erase tab and erase it in "Mac OS Extended (Journaled)". Finally, close Disk Utility and reinstall OS X.
If you have got an older Mac, call Apple to get replacement DVDs > http://support.apple.com/kb/HE57
I change iMac hard disk from basic to dynamic in windows 7
