Right headers to use ms-excel http extention to open php generated html table to open in excel

Good day everyone.

I use PHP to generate tables in HTML, which also shall be able to be exported (for excel). For a while i used datatables to do this. but it is very js heavy and runs endless on bigger tables.
I am aware that excel can read html. But just forcing the HTML table to download would mean my users need to navigate through "open with" in windows to open it in excel. And as some of you might guess, that's to much.

I am also aware that office installs http extension like "ms-excel", so i tried to force the system directly to open the html with excel using "ms-excel:ofv|u|http://intranet/report.php?export=excel"

Unfortunately Excel says it's an unknown command. But if i save it the usual way, put the file up on the Server and try it again with "ms-excel:ofv|u|http://intranet/exported_file.htm" it works.

So i assume the problem lays in the headers, but i can't figure which would be correct. Is one wrong or missing?

header('Content-Description: File Transfer');
header("Content-Type: text/html");
//header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename="exported_'.time().'.htm"');
header('Content-Transfer-Encoding: binary');
header('Connection: Keep-Alive');
header('Expires: 0');
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Pragma: public');
header('Content-Length: 11386');

Alternatively i could save the generated html on the server and provide a link but that far from an elegant solution.

I've found the Problem contrary to my believe it wasn't the headers.
It is the URL. It seems Office ignores the filename that is given in the headers and only looks in the URL. If the file in the URL is a .html or .htm file, it works.

For my case the solution is to tell Apache2 to execute php not only in php files but also in htm and html files. And rename my script.
I am aware that this may raise some security concerns, but in my case its in a customers intranet and i am the only one who put files on it.