Does your Mac meet these minimum requirements for Lion 10.7?:
OS X Lion system requirements
To use Lion, make sure your computer has the following:
- An Intel Core 2 Duo, Core i3, Core i5, Core i7, or Xeon processor
- Mac OS X v10.6.6 or later to install via the Mac App Store (v10.6.8 recommended); you can install without Mac OS X v10.6 by using an OS X Lion USB Thumb Drive, available on the Apple Online Store
- 7 GB of available disk space
- 2 GB of RAM
If your Mac does not meet these requirements, you will need to upgrade your Mac before installing Lion.
Thank you Radiation Mac
I checked all of the above.
It turns out it was not a problem with the imac, but the very large files and slow transmission speed between the US and Australia.
The download failed twice and went through the next day but took about 3 hours.
I think the files are too big for anything as important as an OS, it only takes a momentary glitch for the download to fail. At least apple didn't charge extra for the restarts.
Not sure that I like Mountain Lion better than OSX 10.6 seems to be a few issues with Mail.
Thank you Aleks
I will try this next time, but I finally got the complete file downloaded on the third attempt and have installed it.
I think downloading large files, or streaming, from the US to Sydney Australia is always going to be slow process. I have cable broadband which is reasonably fast, but can't make up for the distance and traffic volume from the northern hemisphere.