microsoft/MIDI rc-3

App SDK and Tools Release Candidate 3 + Basic MIDI 1.0 Loopbacks

Repository: microsoft/MIDI

Tag: rc-3

Published: 2026-02-28T20:17:32Z

Prerelease: yes

Release notes: UPDATE: 2026-03-01: Replaced the SDK & Tools package with a newer one with an updated MIDI Settings App installer to help those who were running into the XamlParseException on Settings app Startup.

IMPORTANT: If you want the MIDI 1.0-style basic loopback endpoints (they work like loopMIDI and similar), you must install the service plugin as well as the SDK Runtime and Tools. If you don't want those, you only need to install the SDK Runtime and Tools package.

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Quality

| Component | Stage | | ------------- | ------ | | App SDK Runtime | Release Candidate. No breaking changes. | | MIDI Settings app | Preview. This is still beta-quality and is in active development | | MIDI Console app | Preview. This is quite stable at this point | | Other tools | Other tools like midi1monitor, mididiag etc. are all stable |

Note: because the runtime is not yet signed, we don't recommend that app developers take dependencies on the preview SDK if they are broadly releasing to customers unless you indicate that the functions you use from the SDK are currently in preview.

Instructions

This is for customers who have Windows MIDI Services enabled on their PC. If you are unsure, use the midicheckservice tool below.

> Be sure to download the correct version for your CPU. Arm64 versions are for Qualcomm Snapdragon and other Arm64 processors. x64 versions are for Intel/AMD processors.

If you want MIDI 1.0-style loopback endpoints, first install the Loopback Endpoints Plugin Preview below. This requires that you first turn on Developer mode in Windows because this preview package is not yet signed, and then leave Developer Mode on to use the loopbacks. For the same reason, your browser and/or OS may warn you multiple times when you install it.

The service plugins below have these names

• Windows.MIDI.Services.Basic.MIDI.1.0.Loopback.Preview.1.0.0-preview.1.2-arm64.exe
• Windows.MIDI.Services.Basic.MIDI.1.0.Loopback.Preview.1.0.0-preview.1.2-x64.exe

> IMPORTANT: If you have the previous preview from Discord, uninstall it first, as it will conflict with this preview. If you accidentally install this without removing the other one, uninstall both, and then install this version.

After installing the service plugin, install the App SDK Runtime and Tools. This will provide the settings app and more.

The SDK Runtime and Tools installers below have these names

• Windows.MIDI.Services.SDK.Runtime.and.Tools.1.0.16-rc.3.3-arm64.exe
• Windows.MIDI.Services.SDK.Runtime.and.Tools.1.0.16-rc.3.3-x64.exe

> If after installing both packages, you open the MIDI Settings app and find that you do not see the MIDI 1.0 loopback endpoints on the left, it likely means that the installer for the plugin was unable to restart the service. The easiest way to handle this is for you to reboot your PC. Those who are familiar with the Services app in Windows can restart the MIDI service from there, after closing all MIDI-using apps including the MIDI Settings app.

Changes

New MIDI 1.0 Loopback Service Plugin

This is a preview of a feature we'll work into Windows in a few months. This can be used like the third-party loopback endpoints you are familiar with today. The important difference compared to the MIDI 2.0 loopbacks is that you can have a single name, and the result is a single MIDI Source/Input and a single MIDI Destination/Out, vs a pair of each.

We're working on the fixes to make loopMIDI and similar virtual devices work again. In the meantime, if all you need is a loopback endpoint, or dozens of loopback endpoints, this will work for you. There is no practical limit to the number of endpoints you can create.

App SDK

• MidiEndpointDeviceInformation has an IsMuted property. Right now, this only applies to basic loopback endpoints, but we're considering supporting this for all types of endpoints in the future.
• Microsoft.Windows.Devices.Midi2.Endpoints.BasicLoopback is the namespace with the new MIDI 1.0 loopback features

MIDI Settings App

The MIDI Settings app checks for Windows MIDI Services feature enablement upon startup.

Support for MIDI 1.0-style loopback endpoints. These work like the third-party loopback endpoints do today, in that you only need to supply a single name. These loopbacks also support muting, which enables you to stop message transmission through the endpoint without removing it. Muted endpoints have a little glyph at the top left of the loopback item on the MIDI 1.0 loopbacks page.

The first time you use the MIDI Settings app, you will be prompted to create a configuration file and the MIDI 2.0 loopbacks, as in the past. However, a default MIDI 1.0 loopback will now be created in addition to the MIDI 2.0 loopbacks.

MIDI Console App

You can now create and remove transient MIDI 1.0 loopbacks.

Known issues and workarounds

This is the blog post with known issues and workarounds: https://devblogs.microsoft.com/windows-music-dev/windows-midi-services-rollout-known-issues-and-workarounds/