If you get HTTP Error 404.3 – Not Found on your IIS 7/7.5/8/8.5 server, it might be because of missing ASP feature. This error may interfere with the proper functioning of your web application, but it can be resolved with the following steps:
HTTP Error 404.3-Not Found
The page you are requesting cannot be served because of the extension configuration.
If the page is script, add a handler. If the file should be downloaded, add a MIME map.
Causes of HTTP Error 404.3:
- It’s possible a handler mapping is absent. By default, the static file handler functions all content.
- Make sure the correct MIME map is allowed for your application or website. Be careful not to create MIME maps for sensitive files like .config or .aspx pages.
- The feature you want to use might not be installed.
- If ASP.NET is not installed.
How to fix HTTP Error 404.3 – Not Found
You need to install IIS sub components from
- Control Panel -> Programs and Features -> Turn Windows features on or off
- Internet Information Services -> World Wide Web Services -> Application Development Features
-
After that, you should check ASP.NET option. After clicking on ASP.NET option ISAPI Filters, ISAPI Extensions, .NET Extensibility options will be selected automatically. Make sure that specific version is checked. These options are divided into 4 and 4.6 in Windows server.
Run the following command from cmd:
For 32bit (x86) Windows:
%windir%\Microsoft.NET\Framework\v4.0.30319\aspnet_regiis.exe -ir
For 64bit (x64) Windows
%windir%\Microsoft.NET\Framework64\v4.0.30319\aspnet_regiis.exe -ir
Note: .NET framework version can be changed. So make sure which framework version is in the %windir%\Microsoft.NET\Framework64 directory and run the command accordingly before running.
Lastly, Check in IIS manager, that your application uses application pool with .NET framework version 4.0. For more details, you can visit Webhosting UK and initiate a live chat.
