My Imac is version 10.6.8 can I up date with OSX Mountain Lion 10.8.4

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OS X Mountain Lion needs a Mid 2007 or newer iMac (iMac7,1 or later as the model identifier) > http://www.apple.com/osx/specs Open the Mac App Store and purchase OS X Mountain Lion. If your computer isn't compatible, the Mac App Store will give you an error message.

While it's being downloaded, make a backup of your files and check that your apps are compatible > http://www.roaringapps.com

When the download finishes, the Mountain Lion installer will appear, so follow the steps.

OS X Mavericks will be launched in fall and will include more features > http://www.apple.com/osx/preview