we install the windows 7, but when we start the mac it will ask to reinstall the MAC OS X or back up from time machine, now what should i do?
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To start on Mac OS, press Option key on boot and choose the OS X partition. If you want to start always in Mac OS X, open System Preferences > Startup Disk and select Macintosh HD
Restart again, press Option key on boot and select Macintosh HD. If OS X Utilities appear, you erased the OS X partition
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