Why midiOutOpen returns 1 (=Unspecified error) in a UWP app?

Question

As soon as I convert the app, the midiOutOpen function starts to return 1 on being called.

I declare it as:

VB
Shared Function midiOutOpen(ByRef lphMidiOut As IntPtr, uDevID As IntPtr, cBack As IntPtr, dwinst As IntPtr, dwFlags As UInt32) As UInt32

Is there a way to use winmm.dll/midiOutOpen from a packaged app( .appx ) that can still be published to MS store? Or some other way to acquire the handle of the midi device (ID 0)?

Answer 1

It looks like the midiOutOpen function and other APIs like midiOutShortMsg function do not work in desktop bridge apps.

Currently, we'd suggest you use the modern MIDI from Windows.Devices.Midi Namespace . You could refer to the sample here: MIDI sample .