Excel paste failures fixed after September security update

Microsoft has fixed a silent bug that stopped Excel from pasting data after last month’s security updates, according to BleepingComputer.

If your office runs Excel 2016, 2019, 2021, 2024, or uses Excel Online, you might have noticed your spreadsheets just… stopped working. You’d copy cells, hit paste, and nothing happened. No error message. No sound. Just the same old empty box staring back at you.

The issue started after customers installed the September 2026 security updates, including KB5002914. Users took to Reddit and Microsoft’s Q&A forums to complain that copy-and-paste, autofill, and formula dragging had gone dark. Microsoft confirmed the problem in a support document updated on Friday.

To get the fix, you have to manually download and install the update for your specific version of Office, according to Microsoft‘s support document.

What to check this week

Here are the specific fixes for each version:

• Excel 2016: Install update KB5002665.
• Office LTSC 2019: Install Build 10417.20208.
• Office LTSC 2021: Install Build 14334.20918.

Office LTSC 2024: Install Build 17932.21000.

If your spreadsheets use conditional formatting (color-coded cells based on values), paste might still fail even after the update. In that case, use the ‘Paste Special’ option instead. Press Ctrl+Alt+V to open the menu, then choose ‘Values’ or ‘Formula’ to get the data in without the formatting glitch.

It’s a hassle to hunt down the right build number, but it’s better than losing an afternoon to a silent spreadsheet. Check your versions and get patched.

Sources: BleepingComputer.