Is Tessian down?

Status: Monitoring Proofpoint investigated elevated error rates processing inbound and outbound emails on our US Server. On June 12 2026 from 14:30 UTC to 16:19 UTC, ~2% of emails sent or received failed to process. Proofpoint Engineering have remediated the issue, and is currently monitoring. For Core Email Protection API - this mean impacted inbound emails were not initially submitted for scoring, did not create a security event, and could not be found in Investigation & Respond. Missed emails are currently being re-submitted, effectively translating to a delay in processing and remediation where applicable. For Adaptive Email DLP - this means reporting for M365 add-in user responses may be temporarily inaccurate on the timeline of a security event. A small percentage of checks done by the M365 Add-in quickly timed out and failed open during the impact window. For customers using the Gateway, these check would have been routed to and completed by the Gateway. Affected components Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Reported Emails (Degraded performance) Investigate and Respond - Email Search (Degraded performance)

Status: Resolved After continued monitoring, all systems remain healthy. Please feel free to open a support case if you have additional questions. Affected components Core Email Protection API (Operational) M365 Add-in (Operational) Reported Emails (Operational) Investigate and Respond - Email Search (Operational)

Status: Investigating We are currently investigating the degradation of some features, including Silent outbound API and the Abuse Mailbox. The team is actively working to mitigate and we will follow up with more details soon. Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Proofpoint API (Degraded performance) Proofpoint Portal (Degraded performance)

Status: Investigating Proofpoint Engineering is actively working to mitigate customer impact. We've engaged 3rd party support to address the cause, and will continue to update on progress.  Full list of potential impact can be found here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-elements-of-Core-Email-Protection-API-and-Adaptive-Email-DLP-03-June-2026 Affected components Reported Emails (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Proofpoint API (Operational) Core Email Protection API (Degraded performance) Proofpoint Portal (Degraded performance)

Status: Identified Proofpoint Engineering is continues to mitigate customer impact per item. We remain engaged 3rd party support to address the cause and resolve the overall issue.  Full list of potential impact can be found here:https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-elements-of-Core-Email-Protection-API-and-Adaptive-Email-DLP-03-June-2026 Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Proofpoint API (Operational) Core Email Protection API (Degraded performance) Proofpoint Portal (Degraded performance) Reported Emails (Degraded performance)

Status: Identified The majority of customer symptoms have been manually mitigated by Proofpoint Engineering. We continue to work with 3rd party support to address the initial cause.  Full list of potential impact can be found here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-elements-of-Core-Email-Protection-API-and-Adaptive-Email-DLP-03-June-2026 Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Proofpoint API (Operational) Core Email Protection API (Operational) Proofpoint Portal (Degraded performance) Reported Emails (Operational)

Status: Monitoring Working with 3rd party vendor support, Proofpoint was able to determine this was caused by a vendor side issue, who have since deployed a fix. The underlying third party issue has been resolved as of 21:30 UTC June 3rd 2026. Proofpoint is continuing to closely monitor a full recovery.  Full list of potential impact can be found here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-elements-of-Core-Email-Protection-API-and-Adaptive-Email-DLP-03-June-2026 Affected components Proofpoint Portal (Degraded performance) Reported Emails (Operational) Proofpoint Cloud Email Security Platform (Degraded performance) Proofpoint API (Operational) Core Email Protection API (Operational)

Status: Resolved Working with 3rd party vendor support, Proofpoint was able to determine this was caused by a vendor side issue, who have since deployed a fix. The underlying third party issue has been resolved as of 21:30 UTC June 3rd 2026. Full list of potential impact can be found here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-elements-of-Core-Email-Protection-API-and-Adaptive-Email-DLP-03-June-2026 Affected components Proofpoint Cloud Email Security Platform (Operational) Proofpoint API (Operational) Core Email Protection API (Operational) Proofpoint Portal (Operational) Reported Emails (Operational)

Status: Investigating We are currently investigating an issue impacting some Core Email Protection API and AEDLP customers. Since 20:48 UTC 28th May 2026, a subset of mailboxes stopped syncing across some customers. A workaround was applied at 02:30 UTC May 29th and we are seeing impacted mailboxes connecting again. We are continuing to work to restore full functionality. The team is working diligently and with urgency on full remediation. Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance)

Status: Identified Proofpoint has identified the cause, and continues to work on a resolution for impacted customers. For full details of the impact, please consult here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 We will continue to update on the progress of resolution via this page and the community article. Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance)

Status: Identified By May 29 2026 - 14:00 UTC, Proofpoint Engineering deployed a potential fix and have been monitoring the results. We have now started to see slow recovery across the impacted customer base. We will continue to monitor and explore options to speed recovery. At this stage in recovery we do not yet have an expected timeline, but will continue to evaluate and provide one as able.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance)

Status: Identified Proofpoint Engineering continues to deploy incremental fixes to speed up recovery, however progress continues slowly. At this time we still do not have an expected timeline, but cross functional teams continue to actively explore all avenues available until we achieve a full recovery.   You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance)

Status: Identified Proofpoint Engineering continues to monitor recovery and aide in efforts, in addition to continued optimization, we have engaged 3rd party vendor support to accelerate recovery where relevant. At this time we still do not have an expected timeline, but cross functional teams continue to actively explore all avenues available until we achieve a full recovery.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance)

Status: Identified Proofpoint Engineering remains engaged with 3rd party vendor support and is actively monitoring recovery. At this time we still do not have an expected timeline, but cross functional teams continue to actively explore all avenues available until we achieve a full recovery.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance)

Status: Identified Proofpoint Engineering identified additional steps to speed up recovery, and has seen positive results after testing and deploying. As of right now, we tentatively estimate the last of impacted mailboxes to recover after 00:00 UTC June 1st, in the early morning hours. As we progress, we will update accordingly.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance)

Status: Identified Proofpoint Engineering continues to monitor recovery, and it remains on track. As of right now, we tentatively estimate the last of impacted mailboxes to recover after 00:00 UTC June 1st, in the early morning hours. As we progress, we will update accordingly. You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance)

Status: Identified Proofpoint Engineering continues to monitor an on track recovery, making adjustments as needed. As of right now, we tentatively estimate the last of impacted mailboxes to recover after 00:00 UTC June 1st, in the early morning hours. As we progress, we will update accordingly.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance)

Status: Identified Proofpoint Engineering continues to monitor as we approach recovery for all mailboxes. As of right now, we tentatively estimate the last of impacted mailboxes to recover after 00:00 UTC June 1st, in the early morning hours. As we progress, we will update accordingly. You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance) Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance)

Status: Identified At this time, the majority of customers and mailboxes have recovered. For a small number of customers, individual mailboxes remain disconnected, and Proofpoint Engineering is investigating each.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Core Email Protection API (Degraded performance) Proofpoint Cloud Email Security Platform (Degraded performance) Core Email Protection API (Degraded performance) M365 Add-in (Degraded performance)

Status: Monitoring Proofpoint Engineering continued to investigate the remaining individual mailboxes overnight, and as of 01-June-2026 07:30 UTC all mailboxes impacted by this Service Interruption are resolved. Proofpoint continues to work on post incident activities and monitoring. As incident is now stable, no further updates will be provided and we will move this to resolved after 24 hours. We'd encourage you to open a Support Case if you have any additional questions or concerns.  You can read the full impact per product, here: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Core-Email-Protection-API-Protection-29-May-2026 Affected components Proofpoint Cloud Email Security Platform (Operational) Core Email Protection API (Operational) M365 Add-in (Operational) Core Email Protection API (Operational)

Status: Resolved All systems remain stable, and Proofpoint continues to work on post incident activities and monitoring. We'd encourage you to open a Support Case if you have any additional questions or concerns.  Affected components Proofpoint Cloud Email Security Platform (Operational) Core Email Protection API (Operational) M365 Add-in (Operational) Core Email Protection API (Operational)

Status: Investigating We are aware of an issue with the Gateway journal servers at the moment. This problem is isolated to journaling and does not affect inbound or outbound mail delivery. Our teams are currently investigating, and we will follow up as soon as we have more information. Affected components Gateway (Partial outage)

Status: Identified The cause of the problem with the Gateway journal servers has been identified and engineering is now rolling out a fix. This problem is limited to journaling only, and does not affect inbound or outbound mail delivery. We will follow up as soon as we have further information. Affected components Gateway (Partial outage)

Status: Monitoring A fix has now been applied in both EU and US regions. Journaling services are recovering. A very small number of tenants in the EU and US are still experiencing issues and we continue to work on finding the cause for those tenants. Journal emails are flowing again for the majority customers, but please bear in mind that some queuing for journaling may persist for affected tenants for a while. This problem is limited to journaling only, and does not affect inbound or outbound mail delivery. Affected components Gateway (Degraded performance)

Status: Resolved As of 00:35 UTC - the small number of remaining Journal servers have returned to operational. Proofpoint will continue to monitor, but please feel free to open a case if you have any additional questions. Affected components Gateway (Operational)

Status: Monitoring Between 07:30 UTC to 08:56 UTC, 13th May 2026 a Gateway outage occurred for customers that manifested as inbound and outbound server status being 'Unavailable'. This has since been resolved and the server statuses should now all be 'Available' once more. Emails in the queue are expected to clear themselves automatically. We are still working through how this happened and will share further details as soon as possible. Please open a support case if you are still experiencing delays. Thank you for your on-going patience. Affected components Gateway (Full outage)

Status: Monitoring Between approximately 07:30 UTC and 08:36 UTC, some customers experienced an outage where inbound and outbound server statuses were shown as 'Unavailable'. The issue was caused by a capacity limitation encountered during the application of a routine security patch. This has been fully resolved — server statuses should now show as 'Available'. Any emails queued during the incident are expected to be delivered automatically without intervention. No data loss occurred, and we anticipate minimal delivery delays. We apologise for any disruption caused, please open a support ticket if you have any questions. We will close this status as resolved after 24 hours monitoring. Affected components Gateway (Operational)

Status: Resolved The team has been monitoring closely for the last day, and no new issues have been observed. If you have not done so already, please open a support case if you have any additional questions or concerns - we're happy to help. Affected components Gateway (Operational)