The "Back" and "Install Now" buttons are grayed out in the 14.04 installer. How do I restore them?
This happens with both, DVD and USB. The issue appears when selecting the keyboard layout, before selecting partition or drive to use or in between. Simply put, the Back, Install or Continue buttons stop working. they are not selectable. The only good thing here is that you do not get both, Back and one of the other buttons grayed out at the same time. So you can go back and forth until the button appears to be clickable.
This is actually a bug so I will close as such. I suspect the fix will appear on 14.04.1
There is a bug report about it here: https://bugs.launchpad.net/ubuntu/+source/ubiquity/+bug/1303945
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