Hi,
Kendo version 2023.3.1010 installed via nuget package manager downloads corrupt excel spreadsheet files on export.
The workaround for it was to manually download jszip.min.js from the following cdn: https://kendo.cdn.telerik.com/2023.3.1010/js/jszip.min.js
and to replace the one in the nuget installed package.
Please verify your jszip that you're shipping with nuget package manager,
Thanks