Is Tessian down?

Between 13:03 UTC and 13:12 UTC, an issue prevented any Custom Policy checks from being performed. During the same period, all Gateway and COM Add-in checks failed, while around 2% of Outbound via API and Office Add-in checks failed outright. The issue has since been resolved, and service functionality was restored at 13:12 UTC. All check types are now processing normally, and we are continuing to monitor the service to ensure ongoing stability.

After close monitoring, all systems remain stable and we have seen no additional issues. Please feel free to open a support case should you have any additional questions or concerns.

After close monitoring, all systems remain stable and we have seen no additional issues. Please feel free to open a support case should you have any additional questions or concerns.

October 23rd 2026 from 17:35 and 17:55 UTC - we experienced a degradation impacting Silent Outbound Checks via API on our US server. Customer who use the Outbound API for silent Adaptive Email DLP checks may notice events missing during this period, if the email would have only been checked by the API. Adaptive Email DLP checks done by all other integrations were not impacted (COM Add-in, M365 Add-in, or Gateway). There is no impact to Inbound Checks. The team worked quickly to restore service. They are currently monitoring and working to backfill Outbound events from 17:35 and 17:55 UTC. We will update once the backfill is completed and close out this incident. In the meantime, please open a support case with any questions.

As of October 26, 2026 12:56 UTC all missing checks from Silent Outbound API from the impact period (October 23rd 2026 from 17:35 to 17:55 UTC) have been backfilled. After some additional monitoring, things remain stable and we are moving this incident to resolved.

Starting October 7th 2026 at ~07:20 UTC Proofpoint began to receive Graph API failures when attempting to create a user's Quarantine folder for Core Email Protection API. Impact: For less than 600 individual mailboxes in total across all customers and environments, this resulted in some emails failing to quarantine. As of October 9th 2026 17:30 UTC all impacted messages have now been quarantined. Remediation: As of October 9th 2026 16:48 UTC - To prevent broader impact, Proofpoint has pushed a change where all quarantined messages are moved to a hidden folder within the user's inbox. This is how quarantine for Core Email Protection API functioned up until July 2026. Although the user can't access this folder, if they go searching for a mail item it may show in the search results. Proofpoint has escalated the issue to Microsoft to understand the initial cause. As impact is now remediated, we will only look to update the quarantine logic back once we are confident we will be able to create the required folder as expected and without error. We will hold this page open in a monitoring state until we have a better understanding of the long term timeline. Feel free to open a support case with any questions or concerns.

As of October 16th 2026 13:30 UTC, Proofpoint restored Quarantine logic for Core Email Protection API to its previous state. After working closely with Microsoft, we were able to restore this functionality and create Quarantine folders without failures. After monitoring for the past few hours without issue, we will now move this to resolved.

We've discovered an issue with the Gateway sending Block notifications to end users. Since August 25 2026 - Any policy set to Block (not Warn), correctly blocked the sending of the email and created a security event. However, if the email was checked by the Gateway, the end user did not receive a notification that their email violated a policy and was blocked. As of September 23 2026 - Our team is correcting the issue across all customers. Block notifications will start sending to end users going forward, and backlogged block notifications from the last month are will go start to go out. For customers using the Gateway who have policies set to block, they may get reports from these end users due to the delay in the notifications. Please feel free to reach out to Support with any questions.

We have begun rolling out a change to restore Gateway block notifications for affected customers. Based on customer feedback, we have limited notification backfills to emails that were blocked within the last 48 hours. As the rollout progresses, some end users may receive delayed block notifications for messages that were blocked during that timeframe. If you have any questions, please contact Support.

We've completed a restore of Gateway block notifications for affected customers. Block notifications are now sending to end users going forward, and backlogged notifications for the last 48 hours have sent. We appreciate your patience, and please feel free to contact support with any additional questions.

Proofpoint is recovering from an issue impacting multiple services: https://proofpoint.my.site.com/community/s/article/Proofpoint-Service-Interruption-Affecting-Cloud-Service-Portal-Access-04-SEP-2026 As a knock-on effect, we have seen a slight delay in a small number of post delivery checks. The system is currently recovering and we will update once all systems are operational.

As of 18:20 UTC, there is no longer any impact to the US servers and all systems are operational.