This issue was being caused by a network attack on an upstream carrier. It has now been mitigated and service has returned to normal.
Our primary mail relay server, artemis.mysyapps.com, is currently experiencing some very high latency. This is resulting in missed connections or connections that are timing out when attempting to relay e-mail. This will impact customers who use scan-to-email from a multifunction device as well as customers who relay application e-mails through this platform. We are investigating the latency and will report back as we have more information.