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

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

application/x-msbinder is a MIME type used by Microsoft Binder. It bundles multiple files into one container.
This type groups documents into a single file. It enables users to keep related files together.
The format is mainly associated with the OBD file, which is seen in legacy Microsoft software.
Key details: For further technical details, you can review information on related file types with the provided OBD extension.

Associated file extensions

.obd

Usage Examples

HTTP Header

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


    Content-Type: application/x-msbinder

HTML

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


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

Associated file extensions

.obd

FAQs

What is the application/x-msbinder MIME type used for?

The MIME type application/x-msbinder represents Microsoft Binder files, a legacy format used to group multiple Office documents (like Word and Excel) into a single container. This format was prevalent in Microsoft Office 95, 97, and 2000 but has since been discontinued. It is primarily associated with the .obd file extension.

How do I configure Apache to serve .obd files correctly?

To ensure your Apache server sends the correct header, add the following line to your .htaccess file or main configuration: AddType application/x-msbinder .obd. This prevents the browser from guessing the content type and ensures the file is handled as a Binder document.

Can web browsers display application/x-msbinder files directly?

No, modern browsers like Chrome, Firefox, and Edge cannot render application/x-msbinder content natively. When a user clicks a link to an .obd file, the browser will typically prompt them to download and save the file to their computer.

How do I enable support for this MIME type in IIS?

In Internet Information Services (IIS), you must manually add the MIME type if it is missing, or the server may return a 404 error for .obd files. Go to MIME Types in the IIS Manager, click Add, set the extension to .obd, and the MIME type to application/x-msbinder.

Are application/x-msbinder files safe to open?

You should handle these files with caution, as they are legacy OLE containers that can technically contain macros or scripts. Since the format is obsolete, modern antivirus definitions might still scan them, but it is best to avoid opening .obd files from untrusted sources.

What should I use instead of application/x-msbinder for modern web projects?

Since Microsoft Binder is obsolete, you should use standard archive formats like ZIP (application/zip) to bundle multiple files together. Alternatively, for document portfolios, a combined PDF file is a more universally supported option.

Why does my computer fail to open an .obd file?

Because Microsoft discontinued Binder support after Office 2000, modern versions of Office do not open these files by default. You may need to find a legacy tool called "Microsoft Unbind" to extract the individual documents contained within the OBD file.

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.