how can i install mountain lion with out any previous os, meaning a bootable cd that formats etc.

Hi there Douglas,

It sounds like you are looking to install Mountain Lion on your iMac. If you had purchased it from the Mac App Store you may be able to find it in your purchases:

Mac App Store: Finding your purchased apps

If not, since it is no longer available for purchase from the Mac App Store you can buy it from the Apple Online Store as well:

OS X Mountain Lion

Please do take note of the requirements for it to make sure your computer is compatible with it:

System Requirements

To install Mountain Lion, you need one of these Macs:

• iMac (Mid 2007 or newer)
• MacBook (Late 2008 Aluminum, or Early 2009 or newer)
• MacBook Pro (Mid/Late 2007 or newer)
• MacBook Air (Late 2008 or newer)
• Mac mini (Early 2009 or newer)
• Mac Pro (Early 2008 or newer)
• Xserve (Early 2009)


Your Mac needs:

• OS X v10.6.8 or OS X Lion already installed
• 2 GB or more of memory
• 8 GB or more of available space

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