Basics of IISExpress


  • We have the following two types of development servers for building, deploying and testing ASP.NET web applications:

    • The ASP.NET Development Server that comes with Visual Studio
    • The IIS Web Server that comes with Windows
  • IIS Express has features of both of the servers mentioned above so now it is easier to build and run ASP.NET sites and applications.
  • IIS Express is the default web server for web application projects in Visual Studio 2012 and Visual Studio 2013.
  • IIS Express works on Windows XP and higher operating systems
  • IISExpress provides the IIS 7.x developer feature-set.
  • IISExpress works on all operating sytems.
  • IISExpress does not require an admin account to debug/run applications using the developement IDE.
  • IISExpress can be installed along with the IIS webserver and ASP.NET development server without any issues.
  • IIS Express is derived from IIS 7 and above and supports the core features of IIS.

Path of IISExpress

IISExpress can be found in systems at the following path:

USERS\devesho\My Documents\IISExpress

Content of IISExpress folder

An important folder is Config with the following:
  • Applicationhost.config
  • Aspnet.config
  • Redirection.config

Applicationhost.config file

The Applicationhost.config file is the heart of IISExpress. It can be found at the location specified above.
To understand the applicationhost.config file let’s create a sample web application.

Sample Application

  • A sample application has the name TestIISEXPRESS

  • After creating a sample application in the step above, the path of the virtual directory will be created on applicationhost.config.

    The corresponding Virtual directory at applicationhost.config:

  • Setting IISExpress from Project properties.

    We can set IISExpress as a default server using project properties.
    We can choose a Radio Button as shown in the screen below.
    For VS2012 this is the default setting.

  • IISExpress on right tray

    After setting IISExpress as a default server and running the application using F5, we would find the following in the right tray of the system.

  • After clicking on "Show All Applications":

  • Project setting using F4:

  • Let’s change the settings for Managed Pipeline Mode from “ Integrated “ to “classic” as in the following:

  • Corresponding changes automatically occur in the applicationhost.config. file as in the following:

More details of applicationhost.config file

  • Default document setting:

  • Managing Application pool

  • Setting MIME types

  • Security Settings


I have explained the basics of IISExpress and it is very easy to work with it.