Microsoft confirms KB5002914 breaks Excel copy and paste

Microsoft has confirmed that the KB5002914 security update can cause copy and paste to fail silently for some Excel users.

The issue affects Microsoft Excel 2024, 2021, 2019, and 2016. Users may also encounter failures with autofill and formula dragging. Microsoft says the source content remains selected while the destination is not modified, with no beep or error message to indicate that the operation failed.

The problems were reported by customers on Reddit and the Microsoft Q&A forums after the update was installed. Microsoft is researching the issue and plans to provide more information in its support document.

Affected users have reported that uninstalling KB5002914 restores copy-and-paste functionality on impacted systems. Microsoft released the update as part of its September 2026 Patch Tuesday security updates, which addressed remote code execution and information disclosure vulnerabilities.