If you see the “The file couldn’t open in protected view” error while opening Microsoft Excel, the solutions listed in this post may help you resolve the issue ...

Right-click the Excel file that you cannot open and select Properties. When the Properties dialog shows up, switch to the Security tab. Hit the Edit button to change permissions. Once the file’s ...

Windows 10 Professional ... different types of data, you can try the VeraCrypt open source download. Excel also allows you to apply more customized security options to your file if necessary.