IIS 7.5 applicationHost.config file is not being updated

I'm currently playing around with the Microsoft.Web.Administration (MWA) namespace in order to adjust our application to configure IIS 7.5 with the new API. I understood that all IIS level changes should be expressed in the following file (I'm on Win2K8-R2):

%WINDIR%\System32\inetsrv\config\applicationHost.config

So, when I use the ServerManager object to commit the configuration changes the file should be updated accordingly.

After adding a new MIME type (programmatic with MWA) I did not see any changes in the applicationHost.config file, but I do see the new MIME type in the IIS manager window and IIS recognizes this MIME type without problems. Even after restating the OS - The config file does not contain the newly added MIME type, but the IIS manager window does list it.

Because my application pools are forced to 32-bit (Enable32BitAppOnWin64 = true), I thought that the related config file should be located under %WINDIR%\SysWOW64\inetsrv\Config, but (if it exists...) - it also does not change after the code commits the updates.

Can someone please explain this? Am I missing something (looking at the wrong file maybe?)? Can someone please shed some light on the SysWOW64\inetsrv\config directory?

This is my code for adding the MIME type:

ServerManager manager = new ServerManager();
ConfigurationElementCollection staticContentCollection = manager
    .GetApplicationHostConfiguration()
    .GetSection("system.webServer/staticContent")
    .GetCollection();

//MIMETypes is a string[] array, each object is {FileExt},{MIMETypeStr}
foreach (string pair in MIMETypes)
{
    string[] mimeProps = pair.Split(',');

    ConfigurationElement mimeTypeEl = staticContentCollection
          .Where(a => 
                   (string)a.Attributes["fileExtension"].Value == mimeProps[0])
          .FirstOrDefault();


    if (mimeTypeEl != null)
    {
        staticContentCollection.Remove(mimeTypeEl);
    }

    ConfigurationElement mimeMapElement = 
                  staticContentCollection.CreateElement("mimeMap");

    mimeMapElement["fileExtension"] = mimeProps[0];
    mimeMapElement["mimeType"] = mimeProps[1];

    staticContentCollection.Add(mimeMapElement);
}

manager.CommitChanges();

//At this point all is working but the config file does not reflect the change

Solution

I just tried your code and it works fine. You are aware that this mime type is being added to the global mime type collection and not to a site?

It also gets added to the end of the <staticContent> list, this list isn't re-sorted when you do ServerManager.CommitChanges().

Also on Windows 2008-R2 the correct location for applicationHost.config is at:

C:\Windows\System32\inetsrv\config

I'm guess you're either using notepad.exe or NotePad2 to open this file (32 bit editors can't open it). Notepad won't reload the file upon a change and NotePad2 needs to be told to display a file change notification (alt-F5), out of the box it won't.

Also try adding something unusual like .xxx, run your update then open the config file and do a search. I guarantee it'll be there.

Update:

Further to your comments below, I'm not sure how you're able to open applicationHost.config using NotePad++ or any 32-bit editor, I certainly can't. Can you download NotePad2 which is a 64-bit editor:

http://www.flos-freeware.ch/notepad2.html

The release candidate works just fine.

On a default install of any 64 bit Windows 2008 or Windows 7 there shouldn't be an applicationHost.config in the C:\Windows\SysWOW64\inetsrv\Config folder. I'm not sure why you'd be seeing one there.