Fixed: "Error opening (MIDI) output device"

Please let our ADS show!

This sites offers only FREE software and it's supported by a few advertisement boxes (no intrusive popups).
Please:

  • disable your AdBlocker by adding CoolSoft website to whitelist
  • give the proper cookie consent
  • enable JavaScript for this website

This seconds wait is to let you update your browser configuration...

Ok, I've done the required changes... now show me your content!
!!! Please enable JavaScript !!!
Posts: 10
Joined: September 2, 2020 - 01:01
Fixed: "Error opening (MIDI) output device"

Hi everybody,

I started getting this error message (attached) whenever I signed in to Windows 11 (using VirtualMIDISynth 2.13.5.0).

I found it was being caused by the two DLLs that VMS auto-loads on sign-in. I deactivated those two startup tasks (using Autoruns), the error stopped, and VMS still loads and works normally when I use it from within my music software.

Just thought you'd like to know, in case anyone else had this problem. Cheers!

Attachments (Only registered users)
VirtualMIDISynth_error_msg.png

Here's my signature, which you'll have to stare at each time I post a message. Woo!

Hier ist meine Signatur, auf die Sie jedes Mal starren müssen, wenn ich eine Nachricht poste. Wow!

Posts: 1985
Joined: March 25, 2012 - 01:19
Re: Fixed: "Error opening (MIDI) output device"
Ander wrote:
I deactivated those two startup tasks (using Autoruns)

If you set VMS to autostart at logon, there should be only one task related to it.
Could you please show the details of the two tasks you've deactivated?

Posts: 10
Joined: September 2, 2020 - 01:01
Re: Fixed: "Error opening (MIDI) output device"

Hi Mr./Ms. Coolsoft, 😊

To answer your question, a start-up entry for VirtualMIDISynth.dll is appearing in each of these keys:

• HKLM\Software\Microsoft\Windows NT\CurrentVersion\Drivers32

• HKLM\Software\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Drivers32

I'm actually using the 64-bit version of VMS, so are those correct? Or could one or both be left over from a previous VMS version? (I've used it for some time now.)

I've now found that if I deactivate the registry entries, VMS (or maybe some protective Windows 11 mechanism) just creates duplicate, activated entries on next boot. So I'm backpedaling on this whole post—there's no point in deactivating them.

Apparently it has nothing to do with the DLLs anyway! After some experimentation (oh well, I didn't want a life anyway, LOL), I've found the error actually occurs if I exited my music software but left VMS running (in the system tray). When I Hibernate the system, then resume, that's when the error occurs.

I'm guessing VMS is looking for the MIDI port that was opened for it—but since my music app is no longer running, it can't find a place to send its sounds. Am I close?

The solution, of course, is to manually close VMS each time. (My music software (Sibelius) runs VMS whenever I use a playback profile that uses it, but doesn't close it.)

I don't suppose there's a way to set VMS so it exits when its calling procedure exits, or something similar? If not, I'll just have to remember to close it each time, but that's no big deal... Just thought I'd ask. Thanks for the great software!

Here's my signature, which you'll have to stare at each time I post a message. Woo!

Hier ist meine Signatur, auf die Sie jedes Mal starren müssen, wenn ich eine Nachricht poste. Wow!

Posts: 10
Joined: September 2, 2020 - 01:01
Re: Fixed: "Error opening (MIDI) output device"

BTW, when I saw the "Goto Last Page" link in your menu at the left, I thought it might be something like this. 😄

Here's my signature, which you'll have to stare at each time I post a message. Woo!

Hier ist meine Signatur, auf die Sie jedes Mal starren müssen, wenn ich eine Nachricht poste. Wow!

Posts: 10
Joined: September 2, 2020 - 01:01
Re: Fixed: "Error opening (MIDI) output device"

Hi again,

Nothing? Do you need more details?

Wonderingly, A.

Here's my signature, which you'll have to stare at each time I post a message. Woo!

Hier ist meine Signatur, auf die Sie jedes Mal starren müssen, wenn ich eine Nachricht poste. Wow!

Posts: 10
Joined: September 2, 2020 - 01:01
Re: Fixed: "Error opening (MIDI) output device"

Hi Claudio: You must've fixed this bug and added "Fixed" to the forum topic, without commenting... Maybe you were just being modest. 😊

Anyway, I did notice that I can now leave VMS running in the system tray, and it doesn't matter if my music software is also running—the VMS error no longer occurs when I resume from Standby or Hibernation.

Thanks for your generous work. I just bought you a couple of beers (or coffees). Cheers, A.

Here's my signature, which you'll have to stare at each time I post a message. Woo!

Hier ist meine Signatur, auf die Sie jedes Mal starren müssen, wenn ich eine Nachricht poste. Wow!

Posts: 1985
Joined: March 25, 2012 - 01:19
Re: Fixed: "Error opening (MIDI) output device"
Ander wrote:
To answer your question, a start-up entry for VirtualMIDISynth.dll is appearing in each of these keys:

• HKLM\Software\Microsoft\Windows NT\CurrentVersion\Drivers32

• HKLM\Software\Wow6432Node\Microsoft\Windows NT\CurrentVersion\Drivers32

Those keys are not startup keys; they're only used by the system to know which MIDI devices are registered and available.
Starting from Win10 they're managed directly by the Sound service; that's why any manual edit gets overwritten.

Ander wrote:
You must've fixed this bug and added "Fixed" to the forum topic, without commenting...

No, I've not... and that's the scariest part of yout post 🙄

I really don't remember having done it... but lately I'm always managing the forum in a hurry.
So it could be I've marked the wrong one 😥.

Thanks for the coffees, really appreciated 👍