No sound on a Windows 7 machine

I’m trying out 3.5 Pro on a Windows 7 machine (I know only Windows 10 is supported, but I only discovered that after installing it). Not only is there no sound in Dorico, but if I run Dorico then sound also stops working in Sibelius 6 and the only way to get it back is to reboot my computer. I wonder if this is an OS issue?

Hm, would expect that it still runs and sounds on Win7. Could you please do Help > Create Diagnostics Report and attach the corresponding zip here? Thanks

Sure, here it is.
Dorico (237 KB)

Actually it screws with the sound on the computer system wide - I just tried watching a video online but it was silent.

Actually, from Dorico perspective everything looks quite normal. The audio driver is set up to play out via “Headset Earphone (Plantronic)”, but you did not install all the sound contents. Therefore HALion Sonic will not be able to load any sound patches and stays mute. But you could try the Metronome, that should sound, if you create a few empty bars and put 4/4 at the front, then press the play button.
But you need the sound contents anyway. So please download and install the Dorico Sound Installer package (though it’s huge).

As to why all other audio gets screwed on your computer, I have no idea. I have never heard of anything like that before. Even from the few people that are still on Win7.

At the risk of causing offence: Have you deactivated the option that allows Dorico to take control of your computer’s sound exclusively? If that checkbox is ticked, nothing else will sound while Dorico is running.

I’m confused as I did download and install the Dorico Sounds Installer package. No metronome sound btw.

Thanks for that, I’ve only been running Dorico for a day and I didn’t know about that option - it has fixed the problem of other apps going silent (though I still have no sounds coming from Dorico).

Sorry that was wrong I now do have the metronome sound.

Then I recommend to run again the installer for the sound contents. If still no instrument playback is happening then, go in Dorico to Edit > Preferences and choose the VST Plug-ins tab, scroll down and click the Reset Audio Engine Data button. Then restart Dorico where upon a rescanning will take place. Create a simple piano project and check if it does sound.
Furthermore, along with Dorico the Steinberg Library Manager does get installed. If you open that one, does it show any sound library as installed?

Thanks for your help ULF - Reset Audio Engine Data fixed the problem.