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This week, Microsoft released its latest security updates for every supported product, and the various components of Microsoft 365 within its office suite received them too. However, the security update KB5002914 aimed at Excel harbors a grave flaw. Once installed, it prevents Excel from copying and pasting normally or from calculating through formula dragging.
A Patch That Broke Ordinary Operations
KB5002914 shipped on September 9, 2026, alongside the Microsoft 365 security updates. Chiefly, it aims to remedy remote code execution and information disclosure issues in Excel. Microsoft’s official support documentation states that the update applies to Excel 2016. Yet judging from user feedback, every version appears affected, including Excel 2016, 2019, 2021, and 2024.
In its update notes, Microsoft explained the symptom precisely. When affected users perform a paste, the source cell remains selected while the destination fills with nothing. Furthermore, the system raises no error prompt and sounds no operational alert. For now, Microsoft has confirmed only the copy-and-paste fault, whereas the formula-dragging problem that users report remains unconfirmed. The company has since logged the bug on its official KB5002914 support page.
Formula Dragging and Cell Moves Also Misbehave
According to community feedback, dragging formulas to calculate data and moving cells likewise malfunction after installing the update. Some users report that the Excel process crashes after a paste and then restarts itself with such speed that the operation merely appears unresponsive. Consequently, the Excel front-end interface never visibly crashes or reloads.
How to Restore Excel for Now
Since Microsoft currently offers no temporary remedy, the simplest fix for office users is to uninstall the update. After removing it and restarting the system, Excel functions normally once more. That said, such security updates bundle a great many vulnerability fixes, so enterprise IT administrators must still weigh the potential security risks before rolling it back.
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