Is Mailprotector Down?

Microsoft reports broad recovery and says it has addressed the underlying issue. It continues to restore service for any remaining affected customers and regions. Mail flow for both Shield and CloudFilter has been operating at normal delivery times. Shield’s Microsoft 365 mailbox notifications are also healthy. --- [2026-11-13T11:18:14.898-05:00] (monitoring) Microsoft reports sustained improvement and continues to address remaining issues. CloudFilter delivery to Microsoft 365 has improved significantly. Previously delayed messages are continuing to be delivered as the queue clears. Shield mail delivery has returned to normal. We’re also restoring the connections that notify Shield about changes in some Microsoft 365 mailboxes. Until those connections are restored, some mailbox activity may take longer to appear in Shield. We’re monitoring both services as recovery continues. --- [2026-11-13T09:09:48.312-05:00] (monitoring) Microsoft reports that its email queues have significantly decreased and are approaching normal levels. It continues to restore affected infrastructure and investigate remaining issues. Shield mail flow has returned to normal delivery times, and its mail queues have caught up. Some Shield feature notifications are still being processed and may be delayed. CloudFilter continues to deliver queued messages to Microsoft 365, though Microsoft is still temporarily deferring some deliveries. We’re continuing to monitor the situation. --- [2026-11-13T08:13:50.980-05:00] (monitoring) Delivery to Microsoft 365 from both Shield and CloudFilter has improved significantly, and delayed messages are being delivered. Shield’s connection to Microsoft 365 mailboxes also appears to be working again. We’re processing the backlog of queued email and mailbox notifications, and some delays may continue while we catch up. Microsoft reports broader improvement in North America and sustained improvement across much of Europe, but says intermittent issues and delivery delays may continue. We’re continuing to monitor the situation. --- [2026-11-12T20:18:16.182-05:00] (identified) Microsoft is testing a configuration change to address an overwhelmed process on affected servers. It has also begun reverting a recent network configuration change and is monitoring the results. Microsoft has not yet confirmed that service has recovered. Shield’s access to Microsoft 365 mailboxes and email delivery to Microsoft 365 through both Shield and CloudFilter remain affected. We’re continuing to monitor the impact and will share updates as more information becomes available. --- [2026-11-12T16:58:17.257-05:00] (identified) Microsoft continues to restart and validate affected servers as it works to restore service. Shield’s access to Microsoft 365 mailboxes and email delivery to Microsoft 365 through both Shield and CloudFilter remain affected. Our changes to isolate Microsoft-bound traffic have improved mail flow to other providers. We’re continuing to monitor the situation and will share updates as more information becomes available. --- [2026-11-12T15:09:55.428-05:00] (identified) We’ve made changes to isolate traffic destined for Microsoft 365 and reduce delays for mail going to other providers. Delivery to Microsoft 365 remains affected. We’re continuing to monitor mail flow. --- [2026-11-12T14:42:53.477-05:00] (identified) Microsoft has begun redistributing connection traffic and restarting affected servers to reduce the impact of its ongoing service disruption. Some connectivity issues and email delivery delays may continue while Microsoft works to restore service. We’re continuing to monitor the impact on Shield and CloudFilter and will share updates as we learn more. --- [2026-11-12T13:38:10.424-05:00] (identified) Microsoft is investigating an Exchange Online issue affecting mailbox access in the Americas. Microsoft is tracking the issue as EX1550543. We’re seeing Microsoft Graph API errors that are affecting Shield’s ability to access Microsoft 365 mailboxes. We’re also seeing Microsoft’s servers temporarily defer messages from Shield and CloudFilter, resulting in email delivery delays for affected Microsoft 365 customers. This issue originates with Microsoft and is not caused by Shield or CloudFilter. Our team is monitoring the impact and investigating options to mitigate delivery delays. We’ll share updates as we learn more.

Outbound emails from CloudFilter's relay are performing as expected. This incident is resolved. --- [2026-10-28T18:58:02.953-04:00] (monitoring) We will continue to monitor the outbound relay. --- [2026-10-28T17:31:57.474-04:00] (investigating) We are investigating the outbound relay delays and connection refusals. The team has added resources to the outbound pool to alleviate the immediate impact.

This incident has been resolved. --- [2026-10-20T14:55:01.372-04:00] (monitoring) The queues are caught up, and we are observing normal mail flow at this time. The rate limiting experienced this morning was a response to abusive mail volume that was exacerbated by the reduction in Microsoft servers communicating with Shield. We will continue to monitor our queues through the business day to ensure processing is stable. --- [2026-10-20T14:21:18.000-04:00] (identified) It appears that a reduction in the number of Microsoft servers communicating with Shield this morning contributed to the per-server volume spike. The team has mitigated the connection timeouts and rate limits, and the queues are draining. We do not have an exact time for when the queues will be emptied, but it appears it should be within the hour, most likely sooner. We are continuing to investigate with a priority of restoring stable and expected mail flow. --- [2026-10-20T13:21:07.287-04:00] (investigating) We are continuing to investigate this issue. --- [2026-10-20T12:32:31.478-04:00] (investigating) We are investigating reports of connection timeouts or rate limiting with some domains using Shield. This is not affecting all mail flow.