Cornerstone incident
Issues Loading Application and Training - US SL5
Cornerstone experienced a notice incident on January 20, 2026 affecting Response Time, lasting 2d 1h. The incident has been resolved; the full update timeline is below.
Affected components
Update timeline
- investigating Jan 20, 2026, 08:31 PM UTC
Customers on the US SL5 swimlane may experience issues loading the application and training content. We are actively investigating the issue and will share an update as soon as additional details are available.
- monitoring Jan 20, 2026, 10:48 PM UTC
The issue has subsided and we are montioring the activity before considering this resolved.
- identified Jan 21, 2026, 03:16 PM UTC
We have observed that some users may still intermittently experience latency. Our engineering teams are actively investigating the root cause and addressing the issue as a priority. We will continue to share regular updates as progress is made.
- monitoring Jan 21, 2026, 03:56 PM UTC
Latency and overall application performance have improved and returned to normal levels. Our team continues to monitor the service closely while also investigating the root cause to ensure full stability. We will share further updates as we make additional progress. Thank you for your patience and understanding.
- resolved Jan 22, 2026, 10:03 PM UTC
Following a period of monitoring, the issue has been fully resolved and application performance remains stable. No further impact has been observed.
- postmortem Feb 05, 2026, 11:32 PM UTC
**Incident Summary:** Between January 20th and January 21st, 2026, clients hosted in US PRD SL5 experienced an issue where training content was unable to load within the portal. **Impact:** Affected users were unable to launch or access training during the incident window, resulting in a temporary disruption to learning activities. **Root Cause Analysis \(RCA\):** The incident was caused by an abnormal increase in internal processing requests, which led to congestion in background processing. As a result, requests required to load training content were delayed or blocked. **Resolution:** Cornerstone engineers implemented immediate controls to stabilize request processing and cleared the internal backlog. Once processing returned to normal levels, training access was fully restored. **Preventive Measures:** To reduce the likelihood of similar incidents in the future, Cornerstone is taking the following actions: * Strengthening internal request handling and queue management * Improving monitoring to detect processing delays earlier * Reviewing safeguards to ensure training access remains available during traffic spikes