microsoft/MIDI rc-2

App SDK and Tools Release Candidate 2

Repository: microsoft/MIDI

Tag: rc-2

Published: 2026-02-20T00:57:10Z

Prerelease: yes

Release notes: This is an interim release primarily to help customers using the recently rolled-out Windows MIDI Services updates in retail Windows 11, so they can easily create loopback endpoints.

As in the previous release candidate (rc1), the Windows MIDI Services app SDK is itself of release candidate quality. The tools (specifically MIDI Settings app) are preview quality.

This release is not signed, so it is not a "go-live" release for app developers. Additionally, customers downloading this release will receive warning dialogs in their browser that must be clicked-through to keep the download.

As a result of not being code signed, you will likely need to:

• Confirm more than once in your browser that you want to actually keep the file
• Turn off smart app control (temporarily) so the installer can install the files.

Changes

App SDK

• Added AreGroupTerminalBlocksUpdated to the MidiEndpointDeviceInformationUpdatedEventArgs type. To avoid breaking compatibility, this is on a new interface IMidiEndpointDeviceInformationUpdatedEventArgs2. Normally, Group Terminal Blocks are immutable. However, this was added in support of the dynamic endpoint updating for drivers/apps like loopMIDI, where virtual group terminal blocks can come and go. From this, you can also infer that the MIDI 1.0 ports associated with this endpoint have changed.

MIDI Settings app

• The MIDI Settings app now checks for feature enablement when starting up
• You can directly specify the names for each side of a loopback endpoint pair. This makes them a more viable alternative to loopMIDI, loopBE, and similar.
• SysEx sender is hidden unless you select the option to "Enable Preview Tools", in the settings page

MIDI Console app

• The MIDI Console app now checks for feature enablement when starting up
• You can now create temporary loopback endpoint pairs using the MIDI console

midi loopback create

Reminder. 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/

> Edit: the previous upload picked up an older version of MIDI Settings. 1.0.15-rc.2.18 is the corrected version.