Office 2016 pro plus - XL copy paste is not functioning (no issue with MS Word)

Excel losing both Paste and the ability to exit copy mode after updates, while Word still works, suggests investigating Excel specifically before treating this as a Windows-wide clipboard failure. The timing alone does not identify which update or component is responsible.
Save your work, close Excel, and test copying between two cells in a new blank workbook. Next, press Windows+R, enter excel /safe, and repeat the same test. Safe mode bypasses several startup customizations and add-ins. If copying works there, restart normally and disable Excel and COM add-ins individually, testing after each change to identify the trigger.
If the problem also occurs in a blank workbook in safe mode, try Office repair and record the exact Excel build and recently installed update numbers. Avoid removing security updates without a confirmed cause. Office 2016 support ended on October 14, 2025, so also plan migration to a supported version.