Feb 19, 2013 12:49 AM|Mikesdotnetting|LINK
does possible to save html content to .xlsx file?
No. You can't create valid .xlsx files like this. You have a number of options: Office Interop,
OpenXML or a third party library. There are a few around, but no free ones that I know of.
Or you can create a blank sheet and use the ACE OleDb provider to insert rows as if it was a database. Then save the result with a new file name and send that the to the client. Here's some help with doing that: http://yoursandmyideas.wordpress.com/2011/02/05/how-to-read-or-write-excel-file-using-ace-oledb-data-provider/