Microsoft blames AI for delayed Exchange update, can’t say when it will arrive

Microsoft has attributed the delay in releasing a crucial update for its Exchange Server Subscription Edition (SE) to an excess of work resulting from AI-driven bug detection. In a recent post last Thursday, the company acknowledged customer inquiries regarding the timeline for the release of Exchange SE Cumulative Update 1 (CU1).

The update was previously expected to launch by the end of 2025 but has been pushed back to the second half of 2026. Exchange SE is the subscription-based version of Microsoft's email server, and a Cumulative Update (CU) encompasses recent bug fixes, alongside potential new features or removal of obsolete code. Microsoft publishes CUs twice a year, and subscribers can opt for CU installation instead of individual patches.

The update's delay, as explained by Microsoft, stems from the team's utilization of AI tools to identify vulnerabilities in the product. The development team is currently addressing reported issues, which include validating if the issues are genuine security threats, reproducing them, fixing them, testing for regressions, and releasing updates on a monthly basis.

Additionally, Microsoft emphasizes its commitment to prioritizing security above all, as a reason for the delay. The Exchange team is working on CU1 while also incorporating the monthly security payload into the internal build, aiming to release it once a stable point is achieved, and there is a month without pressing security updates.

Microsoft's strategy aims to prevent the need for revision and ensure a high-quality release for administrators. However, the company has not provided a precise date for the CU1 release, only reaffirming that it is in progress.