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

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

application/x-msmetafile is assigned to a file type that stores drawing commands as a vector image. It works with WMF files. These files capture a series of instructions used to render graphics in Windows environments.

Used in Windows applications to display vector graphics.
Ensures images can scale without quality loss.
Holds drawing and rendering commands for consistent output.

This MIME type supports legacy systems where precision and scalability are key. For more detailed technical insights, see Wikipedia on Windows Metafile.

Associated file extensions

.wmf

Usage Examples

HTTP Header

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


    Content-Type: application/x-msmetafile

HTML

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


    <a href="file.dat" type="application/x-msmetafile">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-msmetafile');    
      res.end('Content here');    
    }).listen(3000);

Associated file extensions

.wmf

FAQs

Do modern web browsers support application/x-msmetafile?

No, most modern browsers like Chrome, Firefox, and Edge do not natively display application/x-msmetafile content. This format is specific to Windows environments. To display these graphics on the web, you should convert .wmf files to standard web formats like SVG or PNG.

How do I configure Apache to serve WMF files?

To ensure your Apache server correctly identifies .wmf files, add the following line to your .htaccess file or main configuration: AddType application/x-msmetafile .wmf. This ensures that when users click a link to a WMF file, it is delivered with the correct MIME type rather than a generic text or binary type.

What programs can open files with the application/x-msmetafile type?

Files associated with application/x-msmetafile are primarily designed for Microsoft Windows applications. You can open them using Microsoft Paint, Microsoft Office (Word, PowerPoint), or third-party image viewers like IrfanView and XnView.

Are there security risks associated with WMF files?

Yes, historically, the Windows Metafile format has been subject to critical vulnerabilities (such as buffer overflows in the Windows GDI library). While modern Windows versions have patched these issues, you should treat application/x-msmetafile downloads from untrusted sources with caution.

How do I add support for this MIME type in Nginx?

Open your mime.types file (usually located in /etc/nginx/) and add the entry application/x-msmetafile wmf; inside the types { } block. After saving the file, restart Nginx using sudo systemctl restart nginx to apply the changes.

What is the difference between WMF and SVG?

While both are vector formats, WMF (application/x-msmetafile) is a proprietary 16-bit format designed for Windows internals, whereas SVG (image/svg+xml) is an open W3C standard based on XML. SVG is the standard for vector graphics on the web, while WMF is considered a legacy format for local Windows applications.

Why does my browser download the WMF file instead of showing it?

Since browsers cannot render application/x-msmetafile natively, the default behavior is to download the file so the user can open it with a local application. You can force a download prompt by setting the Content-Disposition: attachment header on the server.

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.