Comment 26 for bug 589236

(In reply to comment #25)
> I just applied your patches, and now I get an error, that the helper
> application for the file is missing. Tried it also on an image file, same
> problem on that one.

You only should use the "another approach" patch. Did you do that? I'm not sure how that would trigger your issue. And you get the error immediately when clicking on a download link?