force to download file

["Hiep Nguyen" <hnguyen@xxxxxxxxxxxxxxxx>]

hi all,

i have this on top of my php page:

header("Content-Type: application/vnd.ms-excel");
header("Content-Disposition: inline; filename=excelfile.xls");

but it is not prompt to save the file instead it opens right in IE.

my question is how do i force the browser prompts to save the file?

thanks