How Do I Fix Unable to Launch IIS Express Web Server?

In this tutorial, we will discuss how to fix the issue of being unable to launch the IIS Express web server. This problem can occur due to various reasons, such as incorrect configuration settings or conflicts with other applications on your system.

Step 1: Check if IIS Express is Installed

Before troubleshooting the issue, it is important to ensure that IIS Express is installed on your machine. To check if it is installed, follow these steps:

1. Open Command Prompt: Press Win + R, type cmd, and hit Enter.
2. Type the following command:

iisexpress.exe /?

3. If IIS Express is installed: You will see a list of available commands in the Command Prompt window.
4. If IIS Express is not installed: You can download it from the official Microsoft website and install it on your machine.

Step 2: Check Port Availability

IIS Express uses specific ports to run web applications. Sometimes, these ports might be in use by other applications running on your system, causing conflicts and preventing IIS Express from launching successfully. To check for port availability, follow these steps:

1. Open Command Prompt.
2. Type the following command:

netstat -ano | findstr :{port_number}

3. If a result is displayed: It means that another application is using the specified port number.
4. If no result is displayed: The port is available for IIS Express to use.
5. If a result is displayed:
• Note the process ID (PID): You will need this to identify the application using the port.
• Open Task Manager: Press Ctrl + Shift + Esc to open Task Manager.
• Go to the “Processes” tab: Look for the process ID (PID) noted earlier.
• If you find a process using the port: Terminate or reconfigure that application to free up the port for IIS Express.

Step 3: Check Configuration Settings

If IIS Express is installed and there are no conflicts with port availability, it’s time to check the configuration settings. Incorrect configuration settings can prevent IIS Express from launching properly. Follow these steps to verify the configuration settings:

1. Navigate to your project folder:

cd {project_folder_path}

2. Open the project’s configuration file:

{project_folder_path}\.vs\config\applicationhost.config

• This file contains the configuration settings for your project’s web server.
3. In the configuration file, locate and verify the following settings:

<system.applicationHost>

<sites>

• <site name=”{your_site_name}” id=”{site_id}”>

<bindings>

• <binding protocol=”{http_or_https}” bindingInformation=”:{port}:{localhost_or_ip_address}” />
• Ensure that the correct protocol, port, and localhost/IP address are specified.

</system.applicationHost>

4. If any of the settings are incorrect: Update them to match your project’s requirements.

Step 4: Restart IIS Express

After checking the above steps, it’s time to restart IIS Express to apply the changes. Follow these steps:

1. Open Command Prompt.
2. Type the following command:

iisreset

• This command restarts IIS Express along with all its associated services.

Conclusion

In this tutorial, we discussed how to fix the issue of being unable to launch the IIS Express web server. We covered steps such as checking if IIS Express is installed, verifying port availability, checking configuration settings, and restarting IIS Express. By following these steps, you should be able to resolve the issue and successfully launch your web server using IIS Express.