For regulatory requirements, users are required to have the 'Previewer' access level on certain content to avoid Download permissions.

However, this means the user is unable to use Excel Online Previewer (due to this requiring 'Download' permission), nor open the file in another editor.

Unlike the .XLSX or .XLSM formats, .XLSB files do not generate a PDF conversion, which makes these files fully inaccessible to Previewers.

The request is for .XLSB files to be supported in Box's native Content Preview.