Sending Excel files containing crucial financial and business data has risks. To add a layer of protection, you should learn to password protect an Excel file.

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.

If you would like to make sure that your Excel spreadsheet data is secure this guide will show you how to password protect and hide worksheets ...

Once you lock a cell, you'll be asked to set a password. Excel will ask you for this password if you try to unlock the cell. Visit Business Insider's homepage for more stories.

While password protection and encryption are excellent ways to secure your Excel workbook, they aren't foolproof and may cause compatibility issues with some third-party applications.