I am getting the error below with my Exchange Friends and Family account that was just migrated to Office 365.  I cannot access email from Outlook.com.  I cannot access email from my Windows 8 Phone.  I have can access my admin page from portal.microsoftonline.com, but get the same error message when I click on the Outlook tab.  I get the same error when I go to mail.office365.com.  I am able to access email from the Windows 8 mail app.  According to the email I received, the upgrade occurred on Oct 10.  I have not had access to email, except via the Windows 8 mail client, since Wednesday, October 9.  It is the same for all users on my domain.  I have found several threads and tried the fixes of clearing cache and tried logging in via the websites listed above.

This account can't be used to access Outlook.com