What is MIME type "application/x-msmediaview"?

A MIME type is a string that tells browsers and other tools how to handle a particular kind of file.

application/x-msmediaview is a MIME type used by Microsoft-specific media viewing components. It indicates that the file contains formatted data and instructions for rendering media content within compatible applications.

This MIME type is designed to streamline how media is displayed. It may include layout details, metadata, and control instructions for media content.

Main use: Enables Microsoft media players and viewers to interpret and display custom media presentations.
Other uses: Supports streaming setups, previews, and structured presentation of multimedia elements in a Windows environment.
Technical detail: The file acts as a container, holding both binary data and formatting rules that tell the system how to manage media display.

Files linked to this MIME type include formats such as MVB, M14, and M13. These files are typically specific to Microsoft products and may not operate correctly on non-Microsoft platforms.

For more technical context, check out the IANA Media Types page.

Associated file extensions

.mvb, .m14, .m13

Usage Examples

HTTP Header

When serving content with this MIME type, set the Content-Type header:


    Content-Type: application/x-msmediaview

HTML

In HTML, you can specify the MIME type in various elements:


    <a href="file.dat" type="application/x-msmediaview">Download file</a>

Server-side (Node.js)

Setting the Content-Type header in Node.js:


    const http = require('http');    
    
    http.createServer((req, res) => {    
      res.setHeader('Content-Type', 'application/x-msmediaview');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.mvb, .m14, .m13

FAQs

What applications open files with the MIME type application/x-msmediaview?

These files are primarily associated with legacy Microsoft Multimedia Viewer software and components. You will most commonly encounter this type with the .mvb extension, used for older digital books and multimedia presentations on Windows.

Can I view application/x-msmediaview content in Chrome or Firefox?

No, modern web browsers do not natively support this proprietary Microsoft format. If you click a link pointing to this MIME type, the browser will usually download the file rather than displaying it.

How do I configure an Apache server to serve these files?

To ensure your server sends the correct headers, add the following line to your .htaccess file or global configuration: AddType application/x-msmediaview .mvb .m13 .m14. This helps the client identify the proprietary format.

Is application/x-msmediaview a standard video format?

No, the x- prefix indicates it is a non-standard, proprietary type. Unlike common video types found on mime-type.com, this format acts as a container for layout, metadata, and media control instructions specific to Microsoft viewers.

What does the .mvb extension stand for?

The extension .mvb stands for Multimedia Viewer Book. It is a compiled file format used by the Microsoft Multimedia Viewer to display text, graphics, and sound in a structured, book-like interface.

Are there security risks associated with this MIME type?

Yes, because these files can contain executable instructions and scripts for the media viewer, they can theoretically carry malicious payloads. You should only open .mvb files from trusted sources.

Why am I getting an error saying the file cannot be opened?

This usually happens because the required legacy Microsoft component is missing from your operating system. Since this is an older format, modern versions of Windows (and non-Windows OSs like macOS or Linux) often lack the necessary software to render application/x-msmediaview content.

General FAQ

What is a MIME type?

A MIME (Multipurpose Internet Mail Extensions) type is a standard that indicates the nature and format of a document, file, or assortment of bytes. MIME types are defined and standardized in IETF's RFC 6838.

MIME types are important because they help browsers and servers understand how to process a file. When a browser receives a file from a server, it uses the MIME type to determine how to display or handle the content, whether it's an image to display, a PDF to open in a viewer, or a video to play.

MIME types consist of a type and a subtype, separated by a slash (e.g., text/html, image/jpeg, application/pdf). Some MIME types also include optional parameters.

How do I find the MIME type for a file?

You can check the file extension or use a file identification tool such as file --mime-type on the command line. Many programming languages also provide libraries to detect MIME types.

Why are multiple MIME types listed for one extension?

Different applications and historical conventions may use alternative MIME identifiers for the same kind of file. Showing them all helps ensure compatibility across systems.