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

Dealing with machine-made bug backlog makes it hard to find a moment to deliver promised subscription service Simon Sharwood Simon Sharwood APAC Editor APAC Editor Published mon // UTC Microsoft has blamed extra work created -finders for the delayed release of a major Cumulative Update to Exchange Server Subscription Edition (SE). Redmond’s Exchange team made that admission last Thursday in a post titled “Where is Exchange SE CU1 anyway?” that reveals the software giant is “getting questions from our customers on when they can expect us to release Exchange SE Cumulative Update 1 (CU1).” “After all, in the past we mentioned that it would be released 2026, later updated to ‘second half of 2026’. Where is CU1?” For those of you who came in late, Exchange SE is the subscription version of Microsoft’s email server, and a Cumulative Update (CU) is a new version of the package that includes all recent bug fixes, plus other changes such as new features or removing deprecated code. Microsoft publishes CUs once or twice a year. Some users prefer applying CUs to applying every patch. As Exchange SE is a subscription product, not getting CU in a timely fashion isn’t a great example of why pay-as-you-go software is a great idea. Microsoft explained delays to the arrival of CU1 “Over the last few months, various Microsoft execs made statements explaining how Microsoft is leveraging a variety of AI tools to help find vulnerabilities in our products.” The post says the Exchange development team is “working through reported issues – which includes validation that they are real security issues, reproducing, fixing, testing for regressions / issues after fixes are deployed and releasing updates monthly.” Redmond’s missive also points to Microsoft’s pledge to “prioritize security above all else” as a reason for delays. A reminder: Microsoft adopted that stance after flaws in Exchange led to an attack on Exchange , earning it a tongue-lashing from the US government. They may also wonder when Microsoft will find a month in which there is no “pressing security payload” that takes priority over CU1. Microsoft’s post offers little certainty because it concludes: “In short: Exchange SE CU1 is coming; we do not have a date to give you.