Log in to the general forum first. After you're logged in, then select members from the dropdown in the menu above and then select edit profile. If you try to go straight to the edit profile selection without already being logged in it will throw you to the login page. After you log in from there you'll get that error. But you can still get to the edit profile page from there if you go to any of the forum pages and then continue to navigate to the edit profile page by following the menus above. Just be logged in before you navigate to the edit profile page. It's still a forum error that should be corrected though.