Windows 10 Icon Gone Missing
Solution 1:
I managed to install Windows 10 by using this tool by Microsoft, and creating a bootable medium.
When you need to select your version of Windows 10, do not select the N version and make sure the language matches.
Solution 2:
Your notification will reappear eventually, but it may not be today, or tomorrow, or the next day...
I came across this announcement today when I viewed this old Windows 8 forum post, and I dare say it is showing in various other places:
