CFFILEUPLOAD error in IE on Windows 2008

[Guest]

OK this is a slick little tag and I'm basically using it to do a real basic upload of multiple files into a specific directory. The app is sitting in a directory which is secured using windows authentication on the server side. Works PERFECTLY on my Dev server, but is acting really wierd on my live server. The Dev server is running Windows 2003. Our live server was recently upgraded to Windows 2008.

As I said, on the Dev server this works in all Windows-based browsers(Chrome, FF, IE & Safari), though it doesn't seem to work in Mac-based Safari. On the live server though, it will not work in IE, but DOES work in FF, Chrome and Safari(though still not on the Mac). On IE it actually throws up a windows challenge box. Clicking Cancel on the challenge box gives a 401 error, trying to log in again locks up the browser and requires an End Task.

My thought was that it must be a permissions issue on the server, as 2008 handles security a little differently. I've tried everything, going so far as to give the IUSR account full control of all directories. I've enabled/disabled all the authentication types in every combination I can think of. I do also have a simple form to upload a single file using a regule input/file tag, and that is working fine, so permissions seem like they shouldn't be the issue. Still it is throwing the 401 error.

Could the issue be something in the way the Flash player is trying to communicate to the server? Any ideas of what to try next would be greatly appreciated.

[Guest]

UPDATE:  I just tried adding the IUSR back onto the administration directory of the site and the upload worked perfectly.  I also found out that the IUSR was NOT removed from the appropriate folder on the 2003 dev server.  So it appears that this is the root cause of the issue.  So other than building a security system using CF instead of Windows authentication, which is probably the best long term solution, does anyone have any ideas for working around this problem?  I'm still stumped as to why it doesn't work in IE, but does in other browsers.  Usually IE is the most friendly in this particular regard.