Many updated email clients, including Apple's iOS mail and Microsoft's Outlook, have implemented security upgrades which require a change in the configuration for NetBox users. New configuration guides are availabe on the Client Home page.
UPDATE - As of 22:25 UTC, the issue with authorization for POP, IMAP and Webmail services has been resolved. We believe that the problem did not affect delivery of email, only the authorization process was affected. Some users may experience some slow logins as the system recovers and the sytem is being monitored for any further issues.