Delays Processing Some Inbound and Outbound Emails
Affected: M365 Add-inCore Email Protection APIReported EmailsInvestigate and Respond - Email Search
Tessian Outage History
Tessian is up right nowTessian had 22 outages in the last 2 years totaling 438h 53m of downtime — averaging 0.9 incidents per month.
There were 22 Tessian outages since June 26, 2025 totaling 438h 53m of downtime. Each is summarised below — incident details, duration, and resolution information.
Potential degradation in some features.
Affected: Proofpoint APIProofpoint Cloud Email Security PlatformProofpoint PortalCore Email Protection APIReported Emails
Timeline · 6 updates
We are currently investigating an issue impacting some Core Email Protection API and AEDLP customers.
Affected: Proofpoint Cloud Email Security PlatformM365 Add-inCore Email Protection API
Timeline · 13 updates
Issue with the Gateway journal servers.
Affected: Gateway
Timeline · 4 updates
- investigating May 27, 2026, 08:13 AM UTC
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)
- identified May 27, 2026, 10:55 AM UTC
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)
- monitoring May 27, 2026, 12:52 PM UTC
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)
- resolved May 28, 2026, 12:40 AM UTC
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)
Gateway outage between 07:30 UTC to 08:56 UTC, 13th May 2026
Affected: Gateway
Timeline · 3 updates
- monitoring May 13, 2026, 10:59 AM UTC
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)
- monitoring May 13, 2026, 02:05 PM UTC
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)
- resolved May 14, 2026, 04:33 PM UTC
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)
Reduced Outbound Checks
Affected: Proofpoint APIGatewayProofpoint Cloud Email Security PlatformProofpoint PortalM365 Add-inCOM Add-in for WindowsCore Email Protection APIAEDLP Email Misdelivery ProtectionAEDLP Email Exfiltration ProtectionAEDLP Custom PoliciesReported EmailsInvestigate and Respond - Email Search
Timeline · 1 update
- resolved May 13, 2026, 02:20 PM UTC
Status: Resolved Between 13:55 and 14:20 UTC , we were alerted to an increase in timeouts on our US server for Outbound checks. Outbound emails sent during the impact period may have timed out and sent unchecked. The team quickly took steps to mitigate and will take the appropriate actions to prevent it in the future. Affected components AEDLP Custom Policies (Operational) Proofpoint Cloud Email Security Platform (Operational) Proofpoint API (Operational) AEDLP Email Misdelivery Protection (Operational) AEDLP Email Exfiltration Protection (Operational) Core Email Protection API (Operational) Proofpoint Portal (Operational) Reported Emails (Operational) Investigate and Respond - Email Search (Operational) Gateway (Operational) Core Email Protection API (Operational) M365 Add-in (Operational) COM Add-in for Windows (Operational)
Gateway outage between approximately 07:30 UTC and 08:36 UTC
Affected: Gateway
Timeline · 1 update
- investigating May 13, 2026, 12:10 PM UTC
Status: Investigating 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. Affected components Gateway (Full outage)
Reduced Efficacy of Email Exfiltration for some customers
Affected: Proofpoint APIGatewayProofpoint Cloud Email Security PlatformProofpoint PortalM365 Add-inCOM Add-in for WindowsCore Email Protection APIAEDLP Email Misdelivery ProtectionAEDLP Email Exfiltration ProtectionAEDLP Custom PoliciesReported EmailsInvestigate and Respond - Email Search
Timeline · 1 update
Gateway Connection Issues impacting mailflow for Gsuite Customers
Affected: Gateway
Timeline · 3 updates
Internal Emails Missing from Investigate & Respond
Affected: Investigate and Respond - Email Search
Timeline · 2 updates
Some Core Email Protection (CEPAPI) Security Events unavailable.
Affected: Proofpoint Portal
Timeline · 6 updates
- investigating Mar 02, 2026, 01:59 PM UTC
Status: Investigating In the Core Email Protection (CEPAPI) Security Events view, some threat event details processed cannot be viewed in full. The timeframe for when these events were received and processed is Friday 27th Feb 10:33 am to 2nd March 10:59am For events meeting this criteria, the following error may be displayed: "event details are currently unavailable for this email. We are working on the issue to get it fixed as soon as possible" Engineering is aware of this problem and is currently working on a solution. Affected components Proofpoint Portal (Degraded performance)
- identified Mar 02, 2026, 03:26 PM UTC
Status: Identified As of 14:10 UTC March 2nd - all events and triggered emails from the impact window can now be viewed in the Investigate & Respond tab. Customers are encouraged to review and action impacted events via I&R in the short term. The team is currently working to restore the same emails in the Security Events tab. As a reminder, this impacts triggered emails from Friday 27th Feb 10:33am UTC - Monday 2nd March 10:59am UTC. Affected components Proofpoint Portal (Degraded performance)
- identified Mar 02, 2026, 08:19 PM UTC
Status: Identified Our team has identified a potential way to restore events from Friday 27th Feb 10:33am UTC - Monday 2nd March 10:59am UTC in the Security Events tab. The team is currently conducting rigorous testing, and will look to deploy it over the course of the week if testing goes well. We will update once this restoration is underway. In the meantime, all triggered emails remain available in the Investigate & Respond tab of your portal. Affected components Proofpoint Portal (Degraded performance)
- identified Mar 03, 2026, 03:22 PM UTC
Status: Identified The process to restore missing Security Events has passed all testing, and Proofpoint will begin the remediation process momentarily. We will update again once all Security Events from the impact window have been restored. Affected components Proofpoint Portal (Degraded performance)
- identified Mar 04, 2026, 06:55 PM UTC
Status: Identified As an update, the majority of Security Events have been backfilled successfully. The process continues for a couple final events, and we will update once fully complete and validated. Affected components Proofpoint Portal (Degraded performance)
- resolved Mar 05, 2026, 11:48 AM UTC
Status: Resolved All security events have now been successfully restored and validated. Remediation is now completed. Affected components Proofpoint Portal (Operational)
Slow Defender Checks
Affected: Core Email Protection API
Timeline · 3 updates
- identified Feb 24, 2026, 05:19 PM UTC
Status: Identified Around 4pm UTC we began seeing delayed Defender checks for inbound emails. For API users, emails may experience up to a 600 second delay for emails to be checked and quarantined. We are looking into this and will provide updates here. Affected components Core Email Protection API (Degraded performance)
- monitoring Feb 24, 2026, 06:20 PM UTC
Status: Monitoring We are no longer seeing delays in CEPAPI Defender checks. Our team is continuing to monitor this issue. Affected components Core Email Protection API (Operational)
- resolved Feb 26, 2026, 12:37 PM UTC
Status: Resolved We are no longer seeing delays in Defender checks. Affected components Core Email Protection API (Operational)