Dots in URL causes 404 with ASP.NET mvc and IIS

🌟🆘 Hey there, tech enthusiasts! Having trouble with those pesky dots in your URL causing a 404 error? Don't worry, we've got your back! In this blog post, we'll address the common issues related to dots in your URL with ASP.NET MVC and IIS and provide you with some easy solutions. Let's dive right in! 🚀

✅ The Problem: So, you have a project that requires URLs with dots in the path, but every time you try accessing a URL with a dot, you're greeted with an annoying 404 error. You've already checked your routing configuration, and that seems to be fine. You even tried adding a request filtering configuration to your web.config but, unfortunately, it didn't help. What's going on? 🤔

💡 The Solution: Fear not, dear reader! The issue you're facing is related to the dot being treated as a file extension by IIS, causing it to look for a physical file instead of matching the route in your MVC application. Luckily, there are a couple of straightforward solutions to get those dots working for you. Let's take a look at them! 💪

1️⃣ Solution 1: Disabling Static File Handling By default, IIS intercepts requests for static files such as images, CSS, and JavaScript. This can interfere with your MVC routing. To overcome this, you can disable static file handling for the specific URL pattern containing dots. Here's how you can do it:

<configuration>
  <system.webServer>
    <handlers>
      <remove name="BlockViewHandler" />
      <add name="BlockViewHandler" path="*.mvc" verb="*" preCondition="integratedMode" type="System.Web.HttpNotFoundHandler" />
    </handlers>
    <staticContent>
      <remove fileExtension=".phelps" />
      <mimeMap fileExtension=".phelps" mimeType="text/html" />
    </staticContent>
  </system.webServer>
</configuration>

In the above example, we're removing the static content handling for the .phelps file extension, which is just an example. Replace .phelps with your desired file extension containing the dot.

2️⃣ Solution 2: Allowing Dots in Routes Another option is to configure the route handler to allow dots in the URL. By default, ASP.NET MVC restricts the dot character for security concerns. To enable dots, update your route configuration like this:

public static void RegisterRoutes(RouteCollection routes)
{
    routes.IgnoreRoute("{resource}.axd/{*pathInfo}");

    routes.MapRoute(
        name: "Default",
        url: "{controller}/{action}/{id}",
        defaults: new { controller = "Home", action = "Index", id = UrlParameter.Optional },
        constraints: new { id = @"\d+" }
    ).RouteHandler = new DotFriendlyRouteHandler();
}

The DotFriendlyRouteHandler class is responsible for allowing dots in your URL routes. You can find a sample implementation of this class in an accompanying code snippet here.

✅ The Call-To-Action: Congratulations, you've now learned how to tackle the 404 error caused by dots in your URL with ASP.NET MVC and IIS! Give these solutions a try in your project and wave goodbye to those frustrating errors. If you found this blog post helpful, be sure to share it with your fellow developer friends! 👥😄

Got any other burning tech questions or topics you'd like us to cover? Shoot them our way in the comments section below! We're always here to assist you in your coding adventures. Happy coding! 💻🔥