Last checked September 18, 2026. This guide follows Microsoft’s current support documentation and will need updating if Microsoft expands the fix to more Office versions.
Copy and paste is one of the most basic Excel actions, which makes this bug unusually disruptive. Affected users can copy a cell normally, see the familiar moving border around the source, press Ctrl+V, and then get no result at all. There may be no warning, no beep, and no visible error message.
Microsoft first documented the behavior as a known issue associated with the September 8, 2026 Excel security update KB5002914. The company later released KB5002665 for Excel 2016, but that update is only a partial answer: it applies to MSI-based Excel 2016, and Microsoft says workbooks containing conditional formatting can still experience paste failures.
Quick answer: what should you do first?
- Confirm your Excel version. The KB5002665 fix is specifically documented for Excel 2016 installed with Microsoft Installer (MSI).
- Install KB5002665 if you are on the affected Excel 2016 MSI edition.
- Test a blank workbook without conditional formatting. If paste works there but fails in your real workbook, conditional formatting may be part of the remaining bug.
- Try Paste Special instead of normal paste. Microsoft currently recommends this as the workaround when the issue persists.
- Do not immediately uninstall the September security update. KB5002914 contains security fixes, so rollback has a security trade-off.
What KB5002914 broke
Microsoft’s KB5002914 documentation says that in Excel 2024, 2021, 2019, and 2016, a paste operation can fail silently. The source remains selected while the destination stays unchanged.
That detail matters because this is easy to misdiagnose as a broken keyboard shortcut, corrupt workbook, clipboard failure, or add-in problem. If Ctrl+C appears to work but Ctrl+V does nothing immediately after the September Office updates, this known regression should be on your checklist before you reinstall Office.
Microsoft’s official KB5002914 page: Description of the security update for Excel 2016: September 8, 2026 (KB5002914).
What KB5002665 fixes — and what it does not
On September 16, Microsoft released KB5002665 for Excel 2016. According to Microsoft, this update fixes the known KB5002914 issue that causes certain paste operations to fail silently.
However, there are two important limitations.
| Situation | What Microsoft currently says |
|---|---|
| Excel 2016 MSI-based installation | KB5002665 is available and addresses the silent-paste regression. |
| Excel 2016 Click-to-Run | The standalone KB5002665 package does not apply to this edition. |
| Workbook contains conditional formatting | Paste may still fail even after KB5002665. |
| Excel 2019, 2021, or 2024 | The KB5002665 support article does not describe this package as their fix. |
Microsoft’s current KB5002665 page is here: September 16, 2026, update for Excel 2016 (KB5002665).
How to tell whether conditional formatting is involved
You do not need to remove every rule from an important workbook just to test the theory. Use a controlled comparison.
- Open Excel and create a new blank workbook.
- Type a simple value such as
Testin cell A1. - Copy A1 and paste it into B1.
- If that works, open the workbook where paste fails.
- Check whether the affected worksheet uses Home > Conditional Formatting.
- Try copying and pasting on a simple sheet that does not use conditional formatting.
If paste works in a plain workbook but fails in a worksheet with conditional-formatting rules, that pattern matches the limitation Microsoft currently documents for KB5002665.
Microsoft’s current workaround: use Paste Special
When normal paste still fails, Microsoft recommends using Paste Special. Open it from Home > Paste > Paste Special, or press Ctrl+Alt+V.
Microsoft currently lists these options as possible workarounds:
- Formulas
- Formulas & Number Formatting
- Values
- Values & Number Formatting
- Link
The right option depends on what you are trying to preserve. If you only need the displayed data, Values is often the least complicated test. If formulas matter, try Formulas. This is a workaround, not evidence that the underlying bug has been completely fixed.
Do not reinstall Office first
A reinstall can appear logical when copy and paste suddenly breaks, but it does not address the cause if the same affected update is installed again afterward.
Before reinstalling:
- check your Excel version,
- check whether KB5002914 or KB5002665 is present,
- test a blank workbook,
- test Paste Special, and
- compare a sheet with and without conditional formatting.
Those checks give you more diagnostic information than immediately removing and reinstalling the whole Office suite.
Should you uninstall KB5002914?
Microsoft’s KB5002914 is a security update, so uninstalling or rolling it back removes security fixes along with the regression. For that reason, rollback should not be the first recommendation for a normal home or business user.
If Excel is business-critical and the documented workarounds are unusable, an IT administrator can evaluate the security trade-off and your organization’s update policy. For most users, the safer sequence is to install the latest applicable Office update and use Microsoft’s workaround while monitoring the support page for a complete fix.
What if you use Excel 2019, 2021, or 2024?
Do not assume KB5002665 is intended for your installation just because it fixes the original regression in Excel 2016. Microsoft’s KB5002665 support article specifically describes Excel 2016 and distinguishes MSI installations from Click-to-Run editions.
If you are on Excel 2019, 2021, or 2024 and normal paste still fails, confirm your exact Office build and update channel first. Use Paste Special as the low-risk workaround while Microsoft continues updating its support guidance.
How this differs from the Windows 11 September update bugs
The Excel copy-and-paste regression is an Office update issue. It is separate from the Windows 11 USB-audio regression associated with the same September 2026 patch window. If you are also troubleshooting a USB headset, DAC, or audio interface that shows Code 10 after the Windows update, see our Windows 11 USB Audio Code 10 guide.
A quick diagnostic table
| What you see | Best next step |
|---|---|
| Ctrl+C works but Ctrl+V silently does nothing | Check Office update history and confirm whether the symptom matches KB5002914. |
| Excel 2016 MSI and KB5002914 is installed | Check for KB5002665. |
| KB5002665 is installed but paste still fails | Test whether the workbook contains conditional formatting and try Paste Special. |
| Blank workbook pastes normally | Compare formatting, workbook rules, and the affected worksheet. |
| Excel 2019, 2021, or 2024 | Do not assume the Excel 2016 standalone KB applies; confirm the current update guidance for your version. |
Frequently asked questions
Does KB5002665 completely fix Excel copy and paste?
No. Microsoft says KB5002665 fixes the known silent-paste issue in the affected Excel 2016 MSI scenario, but paste operations might continue to fail when the workbook contains conditional formatting.
Why does Paste Special work when normal paste does not?
The remaining bug does not necessarily block every paste path. Microsoft specifically recommends selected Paste Special modes as a workaround while it continues researching the issue.
Is this a Windows clipboard problem?
Not necessarily. The documented regression is in Excel. If other applications copy and paste normally while Excel fails in the pattern Microsoft describes, the Office update is a stronger lead than the Windows clipboard itself.
Should I remove conditional formatting?
Not as your first step. Use a test workbook or a simple worksheet to confirm the pattern first. Removing production formatting rules can change how an important spreadsheet behaves.
Will reinstalling Excel fix it?
It may not. If the same affected update is reapplied, the symptom can return. Confirm the update and workbook conditions before reinstalling Office.
Official sources
Bottom line: if Excel copy and paste still does not work after the September 2026 updates, do not treat every case as the same problem. KB5002665 is a targeted Excel 2016 MSI fix, and Microsoft still documents a remaining failure scenario involving conditional formatting. Confirm your version, test a simple workbook, and use Paste Special before making disruptive changes.
