How to allow unknown mime types in iis 7

Written by beckw
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Multipurpose Internet Mail Extension (MIME) types are responses that are sent to a user when a resource is requested. This response identifies the type of file that is present, so that the application can decide the appropriate course of action. This is often used in the playback of audio files, where a plug-in for the browser will decide to try playing the file because it received an audio file's MIME type. IIS 7 rejects unknown MIME types by default, preferring instead to return an error to the user saying the resource cannot be found. You can override this behaviour, and serve the file with an "Unknown" MIME type, by configuring the application to do so by using the IIS manager application.

Skill level:
Moderately Easy

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Things you need

  • Windows Server 2008 or Windows Server 2008 R2

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  1. 1

    Click "Start" and type "Internet Information Services." Click "Internet Information Services (IIS) Manager" from the result list.

  2. 2

    Click "Features" to change to the feature view, then double-click "MIME Types."

  3. 3

    Click "Add" in the "Actions" section of the screen, located on the right-side panel.

  4. 4

    Type "*!" as the file extension type. This wild card represents all unknown files.

  5. 5

    Type "application/octet-stream" in the text box labelled "MIME type." This is a generic MIME type that will tell the browser to treat it as a binary file. In all major browsers, this corresponds to asking the user to save the file to their hard drive.

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