Recently a bunch of files I had setup for download via IIS6's web server stopped working. They are a number of setup files ending in ".exe" and were working prior to a few months ago. I have the file permissions set properly, and even enabled browsing in IIS to determine that the paths are indeed correct. I'm not sure if it is related, but the directories with a period stopped working as well. ex: "~/download/ApplicationName/0.9/AppName-setup-0.9.123b2.exe"
When I rename the directory to say 0_9 the browsing works, but the file itself delivers a 404 message from IIS. For now, I've setup FileZilla FTP for anonymous access to these files, but would prefer to continue using IIS. I've considered creating an HTTP handler to serve the .exe files, but would really prefer a configuration solution. I just can't figure out why it isn't working, as all the settings are correct. Directory is setup for read access. "Everyone" has read permissions on the files themselves, and the directory browsing (aside from the folder "0.9" to "0_9" rename) shows the files.
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I should note that I recently used the WebPI to update (uninstalled the old PHP first) PHP, and add ASP.Net 4 support. It may have removed the .exe mapping, I've only recently had users notifying me of the issue, and I was able to repeat it myself. I'll check on the mapping when I can login to the server later (can't from work).
Best Answer
IIS will not serve a file with an extension it does not have a MIME type mapping for - see http://support.microsoft.com/kb/326965 for details including how to edit the mappings.
Have you changed/installed anything that might have removed the MIME mapping for .exe files from IIS at all?
Also, some proxies and security add-ins may block .exe files - have you added or reconfigured anything like that recently?