Hi @Irena Knez ,
Welcome to Q&A forum!
Please go to File>Account in Excel app to check and share the detailed version with us, for example:
According to your description, it seems that all Excel files on your machine have this issue.
- When did this issue start? Have you performed any updates or installations before?
- Can other Office apps copy and paste normally? Such as Word and PowerPoint.
Please try the follwoing steps to check this issue.
- Open an Excel file, and go to Home>click the drop-down option of Clipboard>click Clear All.
- Go to Windows Settings>System>Clipboard>click Clear button to clear clipboard data of Windows.
- Since you have updated and repaired Office, I would suggest that you try to update your Windows system to check again.
If none of the above methods work, please try to create a new Windows administrative account.
Any updates, please let me know.
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