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Open EMU Applications and select Operating Systems from the list on the left. You will see either one of these, but not both. Double click.
On the main section of the EMU Applications window (the right side) you should now see an install available. Similar to how Application installs work just click on the Upgrade and click on the blue Install button. A window will pop up asking you to confirm you want to upgrade. Select the blue Install button once more.
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