IE10 download file : icon stop loading

IE10 download file : icon stop loading

I'm writing a classic HTML webapplication. When a user click on a download
link, I create a file ( should be a long process ~5min ) and send the file
to the browser with the header (content-disposition","attachment; filename
= myfile.xlsx ).
If the request is too long, the loading icon on the tab stopped loading.
But in fact the request continue to be processed and if the user wait 5
minutes, IE ask to download the file and download it correctly. IE9, and
firefox don't have this behaviour and continue to have a loading page
since the request is not finished.
Is someone have the same issue ? and have a workaround ?
Thanks