500 Errors accessing the application
This summary is created by Generative AI and may differ from the actual content.
Overview
Between 15:00 and 16:07 UTC on January 16, 2026, PagerDuty's EU service region experienced elevated 5xx error rates affecting web application access for less than 1% of customers. The incident was caused by the deletion of a legacy Slack integration which left dangling references, causing specific API calls within the web application to fail. Notifications, events, and access via mobile, API, or chat integrations remained unaffected.
Impact
Less than 1% of customers experienced 500 errors when attempting to access the PagerDuty web application in the EU service region. There was no loss of notifications or events, and alternative access methods including the API, mobile app, and chat integrations were fully functional.
Trigger
The manual deletion of the PagerDuty Advance add-on Slack integration in the EU service region at 15:00 UTC, which was part of a cleanup process to unify Slack integrations.
Detection
Rising 5xx error rates were noticed in the EU service region at 15:33 UTC, alongside reports from a small number of customers regarding web application access issues.
Resolution
Responders identified that the deletion left dangling references to the deleted record. A fix was developed, tested, and rolled out to affected accounts, restoring full access by 16:07 UTC.
Root Cause
A hard deletion of the PagerDuty Advance add-on Slack integration left dangling references. Because a web application API call depended on querying customer add-ons, it triggered failures for the subset of customers who previously used that specific integration.