i have this weird issue on Win 2k3 server and IIS:
Iis has several sites, in one of them i need to create a subdir and set up it as web application. I've noticed that if i create new directory and put some .js/.txt file into it, they will not be served by iis (IE gives an error Internet Explorer cannot display the webpage).
If i put the same files in another old site's subdirectory it will show correctly.
By sniffing traffic i've seen that iis reply connection state 200 and then drop completely any connection
http://domain.com/test2/prova.txt
GET /test2/prova.txt HTTP/1.1
Host: domain.com
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.1.7) Gecko/20091221 Firefox/3.5.7 (.NET CLR 3.5.30729)
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: en-us,en;q=0.5
Accept-Encoding: gzip,deflate
Accept-Charset: ISO-8859-1,utf-8;q=0.7,*;q=0.7
Keep-Alive: 300
Connection: keep-alive
HTTP/1.x 200 OK
If i rename file prova.txt in prova.asp for example it showing without problems so it shouldn't be permissions issue.
After making some researches I've found out that it can be caused by missing mime types, I've checked out .txt and .js are present and served by aspnet_isapi.dll. And here comes another weird thing: if i remove mime mapping from directory's properties it's served correctly, but the same thing doesn't work with js.
I'm really beginning to be out of ideas, is there someone who have some hint?
Thanks in advance.
Best Answer
I had the same problem. IIS does something called MIME type filtering. If it dosn't know a specific file extension's MIME type, it returns a 404 error.
On IIS <7: Open the site (or server) properties. Click on the HTTP-Header tab. Click on the MIME Types button. Add the file type * with the MIME type "application/octet-stream".
For IIS 7+: Open IIS manager. Click the server or website. Double-click the MIME Types feature icon. In the Actions pane, click Add. Populate the "File Name Extension" box with * and the MIME Type box with "application/octet-stream".
The same can also be done in your web.config file if you are creating a .NET application.