To get started, will you please head to Events > Settings, copy the System Information at the bottom of the screen and paste it here for me as a private reply? That will help me check your settings and some other information.
And, just to confirm, you already tried the steps outline here, correct?
I checked the setting, visited the site, and it looks like everything is working smoothly now. I clicked around a bit and all the calendar pages and events seemed to be accessible: