What is MIME type "application/x-ms-registry"?

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

application/x-ms-registry is a MIME type tied to files that hold Windows registry data.
These files store the system's configuration settings in a binary format. They are critical for the OS to boot and run applications properly.

Central Config Storage: Keeps system and application settings organized.
System Boot Integrity: Provides necessary data during startup to load proper system configurations.
Backup and Recovery Usage: Serves as a backup source and is used in migrating configurations.

Files using this MIME type are often seen with formats such as DAT and HIV.
They require specialized tools like the Windows Registry Editor to view or modify the settings safely.
For further details, see Windows Registry on Wikipedia.

Associated file extensions

.dat, .hiv

Usage Examples

HTTP Header

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


    Content-Type: application/x-ms-registry

HTML

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


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

Associated file extensions

.dat, .hiv

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.