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.

How to set Expiration Date when sharing Excel files online To set an expiration date when sharing Excel files online, follow these steps: Open Excel Online on your computer.

You can add or remove a password from your Excel spreadsheets through the File tab. You'll do it slightly differently on a Mac and PC.