Configuring Default Documents in IIS 7
Applies To: Windows 7, Windows Server 2008, Windows Server 2008 R2, Windows Vista
If a client accesses your Web site or Web application without specifying a document name (for example, requesting http://www.contoso.com/ instead of http://www.contoso.com/default.html), you can configure IIS to serve a default document, such as default.htm. If you list more than one default document, IIS reviews the default document list (in order) until it finds a match in the directory and then serves the file to the client.
When both default documents and directory browsing are disabled, client browsers receive a 404—File Not Found error because the Web server cannot determine which file to serve and cannot return a directory listing. However, if default documents are disabled but directory browsing is enabled, client browsers receive a directory listing instead of a 404—File Not Found error.
For information about the levels at which you can perform these procedures, and the modules, handlers, and permissions that are required to perform these procedures, see Default Documents Feature Requirements in IIS 7.