how can i upgrade windows 7 on mac ? ( i already bought windows 8 and running windows 7 in partition ?)
I would recommend you don't upgrade to Windows 8 because Apple does not currently support it. There are no Apple drivers for use with Windows 8. I suggest sticking to Windows 7.
If you are still intent on upgrading simply get a Windows 8 upgrade installer, boot into Windows 7, run the upgrader.
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