Angolo di WindowsMicrosoft has confirmed an issue that, following the recent September 2026, may prevent users from normally using some of Excel’s most important features.
The issue specifically affects operations such as copying, pasting, dragging, and duplicating cells and worksheets and may affect Excel 2016, Excel 2019, Excel 2021 and Excel 2024. Microsoft has classified the situation as a known issue and opened advisory OP1470668 in the Microsoft 365 service. The first to discuss this issue was Günter Born in this article, which we mention for accuracy.
Microsoft has published a workaround, applicable to the other platforms without an update patch.
What happens in Excel
The most common behavior is seemingly simple: the user selects a cell or range, uses Copy or the shortcut CTRL+C, then tries to paste the content using CTRL+V.
In some cases, however, the command produces no result.
The original selection may remain highlighted, while the destination cell is not changed. One particularly problematic aspect is that Excel may not display any error message, nor a warning that would help the user understand what went wrong. Microsoft describes this exact behavior on the page dedicated to the known issue.
The issue is not limited to ordinary copying and pasting. Some users may also have difficulty with dragging formulas, duplicating cells or worksheets, and other operations based on copying content. Advisory OP1470668 explicitly refers to copying, pasting, dragging, and duplicating cells and worksheets.
Where the issue originates
According to Microsoft, the cause is a code regression introduced by a recent service update.
The issue first appeared on 8 September 2026 and led Microsoft to develop separate fixes for the different affected versions of Excel.
The situation is therefore particularly tricky because, at first glance, it may seem like a local problem with the installation of Office, the mouse, keyboard, or Windows clipboard.
In reality, when the behavior matches the one described by Microsoft, completely reinstalling Office is not necessarily a solution.
The September 2026
The issue was linked to the security updates distributed during September’s Patch Tuesday 2026.
For Excel 2016, specifically, the issue was associated with update KB5002914, while Microsoft subsequently worked on a specific fix to restore the normal functioning of copy-and-paste operations.
However, the issue does not affect Excel 2016 alone: Microsoft explicitly lists Excel 2016, Excel 2019, Excel 2021 among the affected versions. 2024.
Microsoft releases the fix for Excel 2016
The new development on 16 September 2026 concerns Excel 2016.
Microsoft has published the update in the Download Center:
Microsoft Excel 2016 – KB5002665
The official page gives the publication date as 16 September 2026 and specifies that the update includes the latest fixes for Excel 2016, along with stability and performance improvements.
Both the x64 and x86:
excel2016-kb5002665-fullfile-x64-glb.exeexcel2016-kb5002665-fullfile-x86-glb.exe
packages are available. Microsoft lists their respective sizes as approximately 136,7 MB and 131,6 MB.
Official download
The update can be downloaded directly from the Microsoft Download Center:
Download Microsoft Excel 2016 KB5002665
The package is intended for Excel 2016 installations supported by Microsoft, including Windows 10 and Windows Server versions listed on the official page.
And what about Excel 2019, 2021 and 2024?
The situation is different for the other versions of Excel.
Microsoft had announced that it was developing fixes separately for each of the four affected versions, so the availability of the update for Excel 2016 does not automatically mean that the same package can also be used with Excel 2019, 2021 or 2024.
This is an important point: do not install KB5002665 on a version other than Excel 2016 assuming it is a universal fix.
The latest available Microsoft advisory says that the Excel team was continuing to verify the effectiveness of the fixes and, at the same time, evaluate a temporary workaround while working toward a definitive solution.
What to do if Excel still isn’t working
Before making changes to your Office installation, it is advisable to check which version of Excel is installed and which updates it has received.
For Excel 2016, the first step is to install KB5002665 and then restart Excel.
After installation, it is advisable to test the following again:
Copy → Paste
CTRL+C → CTRL+V
Dragging formulas
Duplicating cells or worksheets
If the issue persists, the installation may not yet have correctly received the fix, or there may be another cause unrelated to the Microsoft bug.
For versions Excel 2019, 2021 and 2024, however, it is advisable to wait and install only the corresponding official corrective update for that version.
Beware of unofficial workarounds
Several workarounds have appeared in Microsoft forums and communities, including rolling back to a previous Office build.
This solution can indeed restore functionality in some scenarios, but it should be considered carefully, especially in a corporate environment, because rolling back may remove recent security updates.
Manually replacing individual Excel files, such as excel.exe, with files taken from an earlier version is not advisable. This kind of procedure can create a mismatched combination of files and introduce further compatibility, stability, or security issues.
So, is the issue fixed?
Partially.
For Excel 2016 is now available KB5002665, published by Microsoft on 16 September 2026.
For the other affected versions, Microsoft continues to manage the issue through advisory OP1470668 and the related corrective updates.
Users of Excel 2019, 2021 or 2024 who suddenly find themselves unable to copy, paste, or drag cells should therefore not consider the issue a fault with their PC: the behavior is consistent with a known bug introduced by a recent Excel update.
The Excel copy-and-paste issue that emerged after the September 2026 updates is real and acknowledged by Microsoft, and the affected versions are officially Excel 2016, Excel 2019, Excel 2021 and Excel 2024.
Microsoft has identified a code regression as the cause of the issue. For Excel 2016 the new update is now available KB5002665, published on 16 September 2026.
For the other versions, users should instead wait and install the corresponding official fix as soon as it becomes available.
For IT administrators, the recommendation is to carefully check the Office version, update channel, and build before rolling back or making manual changes to the installation.
When an update breaks a fundamental feature of a program used every day by millions of people, the problem is not just technical.
It is also an example of how dependent we have become on the software ecosystem we use every day.
I also write about these changes and their potential long-term consequences on Substack.
Subscribe to Angolo di Windows on Substack
