How do I configure Mountain Lion, Airport Extreme to remotely access that harddrive
Is the drive attached to the Airport Extreme?
If so, then you use the Applications -> Utilities -> Airport Utility to configure the disk and make it avaiable.
Once it is properly configured via Airport Utility it should show up in your Finder side-bar as something you can connect to and mount.
If this is not what you are talking about, please provide additional information about what you desire.
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