Microsoft’s Excel Security Patch Makes Paste Fail Silently

KB5002914, Microsoft’s Excel security update from September 8, 2026, can fail copy and paste with no beep and no error. The source cell stays selected. The destination does not change. Microsoft listed the fault as a known issue two days later and is still researching it.

The same package closes Excel remote code execution and information disclosure flaws. For shops still on bought copies of Office, the patched PC is the one that may not move a cell.

The Paste That Fails Without a Sound

Microsoft’s own notes are blunt. In Excel 2024, 2021, 2019, and 2016, the paste operation might fail silently. Users get no beep and no error message. The marching ants can still sit on the copied range while the target stays empty.

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 is researching the issue and will post more information in this article when the information becomes available.

Microsoft, KB5002914 release notes

That quiet miss is the operational risk. A clerk can hit Ctrl+V, glance at a sheet that did not move, and save it anyway. AutoFill and the fill handle are dying on the same machines. In some offices the Esc key will not even clear the copied-cell border.

THE SEPTEMBER EXCEL PATCH CALENDAR

1. September 4, 2026: Microsoft publishes the Excel 2016 standalone installer in the Download Center (136.7 MB for x64, 131.6 MB for x86).
2. September 8, 2026: KB5002914 is dated as the Excel 2016 security update on Patch Tuesday. It replaces update 5002886.
3. September 9, 2026: Windows Update applies the package on many PCs. The first Microsoft Q&A threads open the same morning.
4. September 10, 2026: Microsoft adds the silent-paste known issue to the KB5002914 page.

On some Excel 2016 MSI boxes the miss is not quiet at all. Patana Tanyapongprat, posting on Microsoft Q&A, said Excel terminated and relaunched so fast that Ctrl+V looked like a no-op. The Application event log showed EXCEL.EXE version 16.0.5569.1003 crashing with exception 0xc0000005. It reproduced in a brand-new blank workbook: type A1:A3, copy, paste into C1. Word on the same PC still pasted. A full Office reinstall did not help, because Windows Update put the patch back.

The Update Arrived After Support Ended

Microsoft’s MSI servicing page still carries a hard stop. Office 2016 support ended in October 2025, on October 14, 2025, the same day Office 2019 left support. The company said it may still ship one or more Office 2016 updates after that date, at its sole discretion.

KB5002914 is one of those extra packages, 329 days after the end-of-support date. The Download Center page for the Excel 2016 installer says a flaw could allow code to run from a malicious file if someone opens it. The KB article then lists 29 CVE advisories, spanning Excel remote code execution and information disclosure.

That is the bind for any desk that still lives in Excel 2016. Microsoft already told those customers to move to Microsoft 365 Apps or to Office LTSC 2024. It then shipped one more security update, and that update can take out paste. Office LTSC 2021, which is also in the known-issue list, reaches end of support on October 13, 2026.

The Download Center package applies only to MSI Office 2016. It does not apply to Office 2016 Click-to-Run editions such as Microsoft Office 365 Home. Microsoft’s known issue still names Excel 2024, 2021, 2019, and 2016, the bought and LTSC line. It does not name Microsoft 365 Apps.

Which Excel Versions Does KB5002914 Break?

The KB number is the MSI name. Click-to-Run shops never see KB5002914 in Installed Updates, which is why some admins hunt the wrong panel and still have a dead paste. The broken bits are versioned as Office builds.

REPORTED BUILDS AND ROLLBACK TARGETS

Vijay Kumar, opening a Microsoft Q&A thread on Office 2021, said Ctrl+C and Ctrl+V failed after Version 2108 (Build 14334.20906), dated September 8, 2026. Formula dragging and AutoFill failed with them. Rolling back to Version 2108 (Build 14334.20848) brought paste back. Repair, disabled add-ins, and spare keyboards did not.

The fault is not on every PC. It has shown up on MSI and Click-to-Run installs, on Windows 10 22H2 and Windows 11 25H2, and in empty workbooks as well as live files. It has also refused to appear on some Excel 2019 Click-to-Run boxes. Treat it as a build-specific break, not a global Excel outage.

Whole Offices Lost Copy and Paste Overnight

This is not a one-laptop curiosity. Named admins on Microsoft Q&A are rolling back entire estates, because paste is how those estates move figures.

SHOPS ALREADY ROLLING BACK

• 500 desktops: Mike Pisano said Office 2016 paste died on all 500 of the firm’s PCs, and that cut and paste had already broken once about six months earlier.
• 1,500 computers: An admin posting as FBACHPG98-6666 said Office LTSC 2019 and Office LTSC 2021 were both hit, with a Group Policy rollback underway to 16.0.10417.20197 and 16.0.14334.20806.
• Office LTSC Standard 2021: Tommy Robin said the same paste failure landed there, and that a Click-to-Run downgrade was not available on those boxes.

You broke Office 2016 on all 500 of our desktops!! You broke Cut and Paste 6 months ago, and now broke it again!

Mike Pisano, Microsoft Q&A, September 9, 2026

Pisano said rolling EXCEL.EXE back to 16.0.5561.1001 restored the grid. That is a file swap, not a supported patch removal, and it can leave Office with mixed binaries. The cleaner MSI path is to remove KB5002914 and hide it so Windows Update does not put it back the next night.

One Microsoft Q&A thread collected 70-plus “same question” clicks. The Office 2021 thread collected 100-plus. Those counters are not a census, but they are the public queue Microsoft is answering while it researches the bug.

MSI Uninstalls the Patch; Click-to-Run Rolls Back

Recovery depends on how Office was installed. MSI can drop one KB. Click-to-Run cannot. It can only move the whole Office build, which also moves Word, Outlook, and the rest of the suite.

TWO RESTORE PATHS

Martin Guillou posted an Oarpmany command for Office 16 on Windows 11 and wrote, “This worked for me; copy-and-paste is working again.” The Office product GUID in that command is not universal. It changes with Standard, Professional, and 32-bit SKUs. Brian Dalipsingh had to use a different pair of GUIDs on 32-bit Office 2016. If the command misses, search the registry for 5002914 and plug in the GUIDs that are actually present.

For Office 2021 Click-to-Run, the command that restored paste for Vijay Kumar, and later for Ha Luong Hoang, is to roll back Office 2021 to build 14334.20848 with OfficeC2RClient.exe. Pablo Rendón posted the matching 2024 LTSC target as 16.0.17932.20910, and told admins to turn updates off afterward. Leave updates on, and the next check-in puts the broken build back.

Swapping in an older excel.exe while leaving KB5002914 installed can restore paste and still leave mismatched Office files. That mix can create other stability or security problems. Uninstall or a full build rollback is the cleaner route.

Office 2016 MSI

There is often no Uninstall button next to KB5002914. Suradej hit that wall on September 9. Oarpmany or msiexec is the way around the missing button. After the patch is gone, hide it in Windows Update or it will return.

Click-to-Run and LTSC

If Installed Updates does not list KB5002914, you are probably on Click-to-Run. Check File, Account for the build number, then roll to the last known good build for that channel. Freeze updates until Microsoft ships a corrected one.

The Clipboard Still Has the Copied Cells

The Windows clipboard is not the patient. Excel’s default paste is. Wayne Burrows wrote that Ctrl+C still put data on the clipboard, and Windows+V still showed it. Ctrl+V would not put it back into Excel. He could paste from that clipboard into other apps. Ctrl+X followed by Ctrl+V worked. Ctrl+D and Ctrl+R did not.

John G. Sullivan saw the same split in the paste menu. The default (first) paste choice failed. The second and third choices, formulas or formulas and numbers, still landed. Other desks have kept working with Paste Special, Values, or with a cut, an undo, and then a paste.

WHAT STILL WORKS ON BROKEN BUILDS

• Paste Special, Values: Often lands numbers and text when Ctrl+V does nothing.
• Paste as formulas: The second or third item on the paste split button has worked when the default paste has not.
• Cut then paste: Ctrl+X followed by Ctrl+V has moved cells on machines where copy then paste failed.

Those routes are a way to finish a sheet. They are not a reason to keep a build that can drop a paste with no warning. Values paste also strips formulas, so a range that should have been copied as formulas arrives as dead numbers.

Rolling Back Reopens the File-Open Bugs

KB5002914 exists because Excel will still open other people’s workbooks. Microsoft’s Download Center summary is the file-open case: a crafted file, a user who opens it, then code. The KB page’s 29 CVE listings are the September pile behind that summary. Taking the update off a PC restores paste and puts those holes back in play.

That trade is uglier on Excel 2016 than on LTSC 2024. Microsoft already ended support for Office 2016. It is under no promise to ship a follow-up that both keeps the security fixes and restores paste. LTSC 2021 is weeks from its own end-of-support date. LTSC 2024 still has years on the clock, so a corrected build is a more plausible wait there.

By September 15, 2026, Microsoft had not posted a fixed package and had not given a date. The known-issue paragraph still ends on research. Until that paragraph changes, the working Excel grid is the unpatched one, and the patched one is the grid you cannot trust to move a cell.