With the Excel file open select File in the top-left corner of the screen, followed by Info. Select Protect Workbook, then choose Encrypt with Password.

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.

Want to protect an important Word document or Excel spreadsheet? Here's how to add a password, make documents read-only, and tap into other tricks to safeguard sensitive files.

Locking cells in a Microsoft Excel spreadsheet is a super useful thing to know how to do. It’s used to protect a certain segment or an entire worksheet from being modified by anyone other than ...

Protecting a worksheet in Excel 2003 prevents others users from editing it. For example, if you have tracked and charted your business's sales on a sheet, you will want co-workers to access the ...

You worked hard to put that Excel sheet together, now protect it from unintended damage.