Open the spreadsheet you want to protect in Excel, click the "Review" tab and then click "Protect Sheet" in the Changes group to display the Protect Sheet dialog.

If you have sensitive data you'd like to keep from prying eyes in a Microsoft Excel file, the easiest way to protect it is with Excel's built-in password tools.

There are several options available to you to protect your Excel file with a password. Remember that once you protect the Excel file, you cannot open it without entering the password.

At the file level, you can password protect an Excel workbook in two ways: You can determine who can get in and who can save changes.

How to Unlock Protected Spreadsheets. You can't edit or copy the contents of a protected Excel worksheet unless you first unlock the protection. If unlocking the worksheet doesn't require a ...

A recommended approach to secure your most private documents — whether it’s a PDF, Word file, or Excel spreadsheet — is to lock them with a passcode. While this does help keep sensitive ...