Forum OpenACS Q&A: IE not listening to the MIME type I tell it to

I'm having difficulty with setting up some download file code. I'm trying to let users download files that are stored on the system (in the same way as [new-]file-storage and the code in download-defs.

The above-cited examples serve the files with whatever MIME type ns_guesstype deems appropriate, however that causes types like Word and Acrobat documents to display inside the browser window.

I know this is an Internet Explorer "feature". MS didn't think that programmers would be capable of setting a MIME type so they decided to let IE guess at all times.

I also read about a work-around somewhere, but I can't remember where that article was, or what it said.

Does anyone have any idea what I could do to get IE to *always* show the "Open | Save as..." dialog when a link is followed?

FYI, what I'm doing is: ns_returnfile 200 "*/*" "[gfn_files]/$project_id/ $filename"


try setting the content type to application/octet-stream and see what happens
That doesn't work either.  IE chooses one based on the file extension.
I've been taking some online courses using WebCT ( They had a similar problem with MS docs trying to display in frame windows.  I don't recall how they got around the problem, but you might check out their sample classroom environment --upload then download the files you are having difficulty with.. and see how it works..  It think it changes presentation based on filename extension.

This article claims that in IE 5.0 and higher you can use add a
Content-Disposition header.
Content-Disposition: attachment; filename=myfile.doc