Everything was working fine until recently.
Stats stopped displaying on the dashboard, so I removed the Google authentication and tried to reauthenticate (I've done this in the past).
When I tried to reauthenticate, I got this error from Google:
The page you have requested cannot be displayed. Another site was requesting access to your Google Account, but sent a malformed request. Please contact the site that you were trying to use when you received this message to inform them of the error. A detailed error message follows:
The site "http://sitename.com" has not been registered.