Excel Copy / Paste not work

Hi Phil,

Thank you for sharing the details of the issue.

Microsoft has confirmed a known issue affecting Excel 2016, Excel 2019, Excel 2021, and Excel 2024 following the September 2026 Excel security update. This issue may cause the paste operation to fail without displaying an error, which is consistent with the behavior you described.

Microsoft is currently investigating the issue. I recommend monitoring the following article for the latest information and any permanent resolution: Description of the security update for Excel 2016: September 8, 2026 (KB5002914)

As a temporary workaround, your IT administrator may consider rolling Office back to an earlier, unaffected build, if permitted by your organization’s update and security policies. Since rolling back may remove recent security fixes, this should be reviewed and performed by your IT administrator.

• If you are unsure who your administrator is, please refer to: How do I find my Microsoft 365 admin?

Alternatively, you may wait for Microsoft to release an updated build containing a fix. Once an update becomes available, please install the latest Office updates, restart Excel, and test the Copy and Paste functionality again.

I hope this information is helpful. If you have any further questions or need additional assistance, please feel free to share them in the comments below. I will be happy to help. 

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