How do I add a new file extension / MIME type?

The following article explains how to create a MIME type for a new file extension. MIME types are created in IIS and allow different file extensions to work in a Web browser. For example, if you wish to use Web pages with the .js file extension, you may need to add the application/x-javascript mime type to IIS.


To add a new MIME type, please follow these steps:

1) Log into your server through Remote Desktop Connection (instructions for connecting to your server through RDC can be found here).

2) Click Start, Programs, Administrative Tools, and select Internet Information Services (IIS) Manager.

3) Expand local computer and expand Web Sites.

4) Right click the appropriate website entry and select Properties.

5) On the HTTP Headers tab click MIME Types.

6) Click New.

7) Enter the appropriate information:

8) Click Ok.

You may need to restart the IIS service for the MIME type to begin working. To restart the IIS service, please follow these steps:

  1. Click Start, select Programs, and then click Command Prompt.
  2. Type iisreset and press Enter. This will stop the IIS service and then restart it.

Note: restarting the IIS service will temporarily suspend the web service and prevent websites from working. The reset should only take around 10 - 30 seconds to complete.