MDS File

What are MDS files and how to open them

Are you having problems opening a MDS file or are you simply curious about its contents? We're here to explain the properties of these files and provide you with software that can open or handle your MDS files.

What is a MDS file?

MDS files have multiple uses, and Media Descriptor is one of them. Read more about the other uses further down the page.

Media Descriptor

The files containing the .mds file extension are files that store information describing the formatting of a DVD or CD. The information contained within the MDS files includes data showing how the disc is organized and which tracks are located on the DVD or CD.

The MDS files do not contain any actual audio or video data in and of themselves. Instead, the MDS files are connected to an associated ISO or MDF file. The ISO or MDF files are the files that contain the actual data that the MDS file is used to reference.

How to open MDS files

We have identified five MDS openers that are compatible with this specific type of MDS file.

Programs that open Media Descriptor files

Last updated: August 9, 2026

All known file formats using extension .MDS

While Media Descriptor is a popular type of MDS-file, we know of 3 different uses of the .MDS file extension. Different software may use files with the same extension for different types of data.

MIDI Stream

MIDI Stream (.MDS) is a RIFF-based stream format that contains musical performance instructions rather than recorded audio. It wraps a standard MIDI (SMF) sequence inside a container that allows metadata or other non-MIDI chunks to be included and still lets software identify and play the embedded MIDI data. The format is occasionally encountered in older game files or multimedia titles and is not widely used today.

CyberLink PowerDVD is known to support .MDS files of this type, which appear among its list of supported media file formats. PowerDVD treats them like other MIDI or musical playback files rather than as disc image sidecars. The .MDS file is produced by games or multimedia content providers that require a wrapper for a MIDI stream to include additional RIFF chunks. On playback, tools that know the format ignore non-MIDI RIFF chunks and extract the SMF-style MIDI instructions for synthesis or rendering.

Files of this format begin with a RIFF header ("RIFF" at byte offset 0) followed by ASCII "MIDSfmt" at offset 8. These signatures help distinguish the stream's metadata and MIDI data structure from other RIFF wrappers.

MDS opener for Windows

We have identified one MDS opener that is compatible with this specific type of MDS file.

TestComplete Project

A TestComplete Project (.mds) file is a file used by SmartBear's TestComplete to store the core settings for a single test project. It captures the information that's shared by all testers - such as the names of project items, which scripting language is used, the list of tests and their structure, and settings relevant to running those tests. It does not include tester-specific details like breakpoints or log file paths.

This file is created when you make a new project in TestComplete, and the ".mds" extension is automatically added. Once saved, TestComplete (or anyone collaborating on the project) uses it to manage project-wide data. Other files in the project folder store the tester-specific configurations (.tcLS), log-related metadata (.tcLogs), and resources belonging to individual project items (scripts, keyword tests, name mapping, etc.).

The .mds file is in a binary format and is not meant for manual editing. It holds references to other files that make up the project but does not embed all project data itself. Its structure is internal to TestComplete, which reads it to reconstruct the project in its IDE.

Programs that open these MDS files

We have identified one MDS opener that is compatible with this specific type of MDS file.

Various apps that use files with this extension

These apps are known to open certain types of MDS files. Remember, different programs may use MDS files for different purposes, so you may need to try out a few of them to be able to open your specific file.

Help us help others

File.org helps thousands of users every day, and we would love to hear from you if you have additional information about MDS file formats, example files, or compatible programs. Please use the links below or email us at submit@file.org to discuss further.