Hi Allan,
When I am trying to open excel using Internet Explorer, it shows me an error message saying 'we found a problem with some content...' and opens excel with no data. but when I am trying to open excel using chrome, excel sheet displays data. To understand the issue I have taken one of your examples. please try to open excel below URL in both chrome and internet explorer.
https://datatables.net/extensions/buttons/examples/html5/simple.html
For more information, I have attached two screenshots in which one is download chrome and another using Internet Explorer.
Internet Explorer Version 11.
Thanks in advance!