Error occurred opening output device for MIDI device VirtualMIDISynth#1

VMS stopped working unexpectedly with this error: Error occurred opening output device for MIDI device VirtualMIDISynth#1

Had not reinstalled the product or used any new tools. VMS will not start up. What can I apply in the way of data to debug?

I saw an example of a person who did a complete manual reinstall and that fixed their problem. I followed that procedure exactly, and that didn't work for me. This is the first significant problem I've seen with VMS and I have been using it for years.

Thanks for your assistance,

David Berning

Thanks for the reply. Have been puzzling over this problem for a while.

Maybe this will help someone else:

I have a Focusrite audio device which uses an Focusrite ASIO driver. Some of the errors I was seeing talked about ASIO, so I did some looking and found there was a newer ASIO driver for the device. I installed it (with some trepidation ;) and the problem seems to have been corrected. Errors seemed to occur when the computer was put to sleep. There might also have been some threading errors in the driver. It seemed like the more open VMS devices, the more the errors happened.

BTW, I am a software developer. I like the VMS product - it must be fairly complicated. It would be awesome if it could output audio, but that might not be easy or possible.

I appreciate that there is support for it. 😁

Windows usually (r)enumerates devices when returning from hibernate/sleep state. // Depends on how deep the sleep state is 😂
Software that rescan the device's name and number and uses windows dll's are not affected. 
// Adding "Use default output device" as an option may resolve this issue. (I'm guessing the default output device is always #1).

But some software such as Musescore and Audacity are known to have the similar problems.
Workarounds for those software are: Transport>"Rescan for audio devices" (for Audacity) and Edit->Preferences>I/O "Restart Audio and MIDI Drivers" (for Musecore).
Maybe consider putting a similar button in VMS?

What I wrote is my experience and thoughts on the subject, maybe it's meaningless 🤓

coolsoft wrote:

That key holds the configured output device for each VMS device.
Now close VMS and add a semicolon in front of that line to make it read like

[Advanced]
...
; OutputDevice=...
...

then restart VMS.

It should now use the default output device.

If this fixes the bug, please let me know the non-working value that was in that key...

Hello, first time posting here; so the first thing I want to express ever is: Thank you so much for VirtualMidiSoft.

I just started to have this issue. The last time I used VMS I was using version 2.13.2, and with that version I got the error yesterday. The first thing I did was update to 2.13.9 but I still got the error with this; effectively, the error happened when resuming from hibernation (Windows 10).

This is how it looked for me, before editing the file:

[Advanced]

LangID=1033

OutputDeviceName=<unknown>

And this, how it looks after restarting VMS (and checking it does work again):

[Advanced]

LangID=1033

OutputDeviceName=<unknown>

; OutputDeviceName=<unknown>

In my case, the output device in use when the system was hibernated (and on resuming) is indeed the HDMI port of the GPU card (GT 730).

I know this thread is almost 3 years old, but If a fix was implemented in the current version, it seems it doesn't work in my configuration. :(