If you have mistyped url and got this error message, everything is ok. If you see this message on your root page, that means there is no page in current zone.

Common ways to do that (get an Page doesn't exist error):

• create new zone (menu) and place it on the top of all zones
• create new language
• delete or hide all pages

Go to Developer -> Zones and see what zone is first in zones list. Then go to Standard -> Menu management and create at least one page for your first zone.