Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
How To Install Mac OS X Mountain Lion With Out Internet
Last year when Apple launched OS X Lion they also launched a USB stick which meant you did not have have an internet connection to download the operating system but this year Apple has choose not to do this for OS X Mountain Lion but instead have come up with another solution for Mac users who are not connect to the internet.
Apple is opening its Apple Retail store’s WIFI networks to customers who would like to download OS X Mountain Lion. This seams to be a fine solution for Macbook users but iMac users and Mac Pro users could face some difficulties.
Another point is how is the networks and internet infrastructure going to handle a lot of people downloading the huge 4.35GB
If you do have the internet you can download Mac OS X Mountain Lion HERE
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