If you protect the workbook structure, users cannot insert, delete, rename, move, copy, hide or unhide worksheets anymore.
1. Open a workbook.
2. On the Review tab, in the Changes group, click Protect Workbook.
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3. Check Structure, enter a password and click OK.
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Note: The Windows option is not available in Excel 2013 and later versions.
4. Reenter the password and click on OK.
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Users cannot insert, delete, rename, move, copy, hide or unhide worksheets anymore.
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Note: to unprotect the workbook, click Protect Workbook and enter the password. The password for the downloadable Excel file is "easy".
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