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.

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.

By default, this property is set to `xlSheetVisible`, which means the worksheet is visible in the Excel interface. To hide the worksheet, change the “Visible” property to `xlSheetVeryHidden`.

Learn how to unprotect Excel sheets or workbooks without a password using this simple step-by-step guide. No software required!

If multiple users work in the same Microsoft Excel file, you can limit their access to only the ranges where they need to work.

I tried to set a password on it again, but I’m getting the following error: “This workbook contains Excel 4.0 macros or Excel 5.0 modules.