On January 23, 2024, starting at 16:04 CET, users in our West Europe (Production 0) region were affected by an issue caused by the migration to partitioned cookies. The problem impacted a subset of users who had their browsers or office applications open during the update process. The issue manifested as infinite web page reloading for the affected users. To address the problem, users were advised to restart both browsers and Microsoft Office.
Following a detailed investigation, the engineering team identified the root cause and successfully implemented a solution that resolved the infinite reloading without requiring user intervention. The solution was deployed, and by 22:04 CET, the problem was mitigated.
Subsequently, a comprehensive review led to the definition of actions and procedures aimed at enhancing the resiliency of our system against similar changes.