On September 8, Microsoft rolled out KB5002914 for Excel, but it apparently has a bug that makes it impossible to copy and paste in certain cases. Microsoft confirmed it’s aware of the issue, which affects all supported versions of Excel, including Excel 2016, 2019, 2021, and 2024.
This comes days after Windows 11’s September 2026 update killed audio, Remote Desktop, and caused havoc on some AMD PCs. Microsoft is apparently having a tough time with September 2026 security updates across its product line, and it’s likely because it’s an extensive release with AI-assisted fixes.
KB5002914 is a security update for Excel, and it patched over 29 security issues, which is why it was automatically applied to all PCs. But as soon as users installed it, they noticed copy and paste was broken. Users also told me that dragging cells to copy formulas stopped working, but Microsoft has not confirmed the second bug yet.
How Excel broke copy and paste with the September 2026 update
After the update, if you copy a cell and try to paste it into another sheet or even on the same sheet, Excel can simply do nothing. The bug persists even if you open another instance of Excel and try pasting there. In our tests, we noticed that the original cells remain selected when you copy, and there’s no error suggesting that nothing was copied.
It’s actually not rare for Excel to fail at copying and pasting, but that usually happens due to a Windows design choice. On Windows 11 (and older versions), if you copy and try pasting while the clipboard is locked by another process, the paste fails.
So you might have had a similar copy and paste issue with Excel in the past, but that was largely due to Windows. This one is an Excel-specific issue, as copy and paste works across Windows unless another process has locked the clipboard.
Microsoft admitted that it broke copy and paste and noted in updated documentation that all supported versions of Excel are affected.
“In Microsoft Excel 2024, 2021, 2019, and 2016, the paste operation might fail silently. Although users try to paste content, the source remains selected and the destination is unmodified. When this issue occurs, users receive no indication of the failure, such as a beep or error message,” Microsoft explained in a document.
Microsoft says it is investigating and isn’t aware of any workaround for now, so if you’ve run into the Excel issue, there’s not much the company can do for you at the moment. It’s also not recommended to remove recent updates due to the severe security fixes included in them.
Excel’s copy and paste problem is widespread
Microsoft appears to have broken Excel’s copy and paste across thousands of installations, so the issue is clearly widespread.
We first saw reports around September 9, a day after the September 8 security update was released, and there are complaints all over Reddit and Microsoft’s own forums.
In a forum post, one user noted that they had issues with older versions of Excel as well, including Office Standard 2016 64-bit. In this specific version, the user said they could reproduce the problem in a completely new workbook. For example, when they entered values into A1:A3, copied them, and tried to paste them into C1, Excel simply did nothing.
In another case, Excel crashed and relaunched on its own, and there was a pop-up confirming the operation failed. If Excel crashes on your PC as well, you can use Event Viewer to track down Excel-related activity. One user found Excel.exe version 16.0.5569.1003 and exception code 0xc0000005 in Event Viewer.
Also, as I noted above, it’s an Excel problem, so different versions of Windows have run into the issue, including Windows 10 22H2 and Windows 11 25H2.
“I spent almost the whole day with the IT team at my company trying to figure this out,” one affected user wrote in a separate discussion.
How to fix Excel’s copy and paste issue after September 2026 update (KB5002914)
1. Use Paste Special
If you’re unable to copy and paste using the usual keyboard shortcuts, you can try to paste values or formulas separately.
To do this, just copy the cells you need and select the destination cell. Now, try using Ctrl+Alt+V, and it’ll open Paste Special, where you can choose Values or Formulas. In my case, since I was copying values, I selected Values and clicked OK.
Also, if you don’t use Paste Special frequently, remember that “Values” and “Formulas” are pasted differently. When you choose Values, it pastes the displayed results and does not try to calculate anything. So if you end up pasting a calculated number using Values in Paste Special, it becomes a fixed value in the destination.
On the other hand, Formulas retains the formulas but does not preserve all of the source formatting.
2. Use Microsoft Word as a medium
Microsoft Word can recognize Excel content, and it can act as a medium to copy and paste across sheets. You just need to copy the Excel content, paste it into Word, copy it again from Word, and then paste it back into Excel.
But you may not preserve formulas or all formatting in most cases.
3. Roll back the Office update
The other option is to roll back the Office update, which is not something you should attempt given the 29 security fixes.
It’s a sad state of affairs for Microsoft Excel, and it’s also quite unfortunate that the company has no immediate fix for an issue that has been reported for over a week.
We’re expecting Microsoft to release an emergency update in the coming weeks
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