Recently I have finally upgraded to Windows Vista from Windows XP. Except regular trouble of upgrading your operation system that feels like moving to a new house (which is people say worse then an earthquake and flooding together) I was quite frustrated by a number of annoying problems with IIS 7 when first it's not installed by default (all right, security is tougher now, but can I at least have an option?), then not all of the components installed that required by ASP.NET and VS2008 (is it so difficult to suggest a correct package?), then again my web app does not work with the default App Domain (why did you guys call it "default" and the real default call "classic"?), and finally everything works but the site does not look like it should be.
I spent some time probing different setting of IIS and finally gave up and looked it up on the Internet. What a relief! It's a Microsoft bug and not me being an idiot! Actually it was submitted on March 17, 2007 and still not in SP1.
So the problem was that the entire static content of the web app including images and styles was not returning to a browser by IIS (content length 0 bytes) because IIS 7 initial configuration was incorrect when it was first installed on Vista.
I am not describing a fix here, read it here: http://support.microsoft.com/kb/930901/en-us