19. March 2021
Behind the scenes the “default.aspx” is being searched for; if you put a /default.aspx at the end of the URL you will find that the page will load.
The fix is to go into the site settings and set the “Default Doc” to default.aspx. In my case I had to manually cut the default.aspx from the last position (figure 2) and then paste it above index.aspx. Once I did this the site started working as expected