We used to host our website on IIS5, and use SoftArtisans FileManager
to download files. It worked great.

We moved the site to an IIS6 machine recently, and now ZIP files won't
download, they are corrupt in IE only. IE 7 downloads them ok, but no
version earlier. and FireFox has no issue downloading them.

The code has not changed either. The file is valid on the server, and
if I make the file directly downloadable (ie.
[url]www.somesite.com/thisfile.zip[/url]) both IE/FF work.

The file sizes on tested files are drastically different. For example,
one file has a size of 50K (which is right) in FF, but 80K in IE.
Looking at the files in textpad, the IE version is totally off. In FF
you can see the filenames contained in the zip.

I've tried overriding the MIME types (as suggested here -
[url]http://www.munit.co.uk/blog/2006/02/22/downloading-zip-files-from-windows-2003-server-and-internet-explorer/[/url])
but that doesn't seem to work either.

Perhaps I'm doing something wrong? Thanks for the help.