So do we. Dorico just works equally well without HALion Sonic, Groove Agent and all the contents downloads, they are all just optional. We recommend to use them, because people also expect from a notation program to have at least a halfway decent playback systems right from the start. But there are also a lot of Dorico users out there that ditch HALion Sonic completely and only use e.g. NotePerformer for playback.
I still hope you can sort it out and get that iso mounted.
Ok, I’ve finally gotten Dorico up and running so just wanted to wrap up this thread. I luckily had an old laptop with Mojave installed which was able to open the iso file. (Seriously, a 6 year old operating system? Steinberg really needs to fix this). Anyway I’ve got it running but I still get a dialog saying that an “essential component” is not found (I’ve attached a screenshot). It doesn’t say what the component is, but things seem to be running ok anyway. So I’ve been spending some time reading the Help documentation and am pretty impressed. It is definitely different than Finale but seems to be much better thought out. Finale had kind of been in a rut for a while and was irritating me more and more. I think I’m really going to like Dorico (fingers crossed). Anyway, thanks so much to all that were willing to help. Now I can restrict my posts/questions to issues about music notation! Best to all.
Hi @tony.byrne , glad to hear that you are now up and running.
In regards to that warning message, could you please choose from the Dorico menu Help > Create Diagnostic Report and attach the corresponding zip file to a reply here? From the contained log data, we might find what is missing.
Already did that. 
Of course I’m still waiting for a reply from issues I raised 3 weeks ago, so we’ll see what happens. I’ve re-run the installer and so I can’t see what would be missing. But let me know if you find out anything.
Thanks, Ulf.
Hi @tony.byrne , I’m sorry, we are getting currently so many support requests, I start losing track. Could you please send me a new diagnostic report again, please. Thank you for your understanding.
I understand. Probably lots of cranky former Finale users like me.
I looked through the logs and found the likely culprit:
2024-09-25 20:45:52.668 [info] Missing content: FCPSMT005ReverenceImpulseLibrary03.vstsound
2024-09-25 20:45:52.668 [info] Missing content: FCPSMT005ReverenceImpulseLibrary04.vstsound
Where would I find those vstsound files?
And I’ll go ahead and submit the full diagnostic report.
Thanks Ulf!
Hi @tony.byrne , okay, those two vstsound files are for the REVerence reverb plug-in, they contain the impulse responses which are needed to calculate the reverb signal.
As a first attempt, go to the Steinberg Download Assistant and click the Install again button for the first item, that means reinstall Dorico, but only Dorico, not the others.
I hope then the alert message is gone. If not, we have other means, but lets try that first.
Hi Ulf,
As a reminder, the Steinberg Download Assistant hangs in Safari and doesn’t work for me (we’ve already covered that). So I just ran the Dorico 5 installer again and get the same result. I think you’ve probably got a problem with the installer. I’m attaching another screenshot that shows the contents of the Dorico_5.1.51_Installer_mac.dmg that I downloaded. I don’t see any trace of those 2 files that are missing. Maybe this will help.
Hi @tony.byrne , but there they are. You see the 3 vstsound files? You need to copy them to
/Library/Application Support/Steinberg/Content/VSTSound
(please note the leading slash, so that path starts in the root of your system harddrive.) After you’ve copied those 3 files, do a double click on one of them, that’s it. If you need further assistance, let me know.
Download Assistant has never worked for me (Mac, various OSs, Safari). I’m very happy it is possible to manually download the installers.
Paolo
I hear ya Paolo_T. I think they’re doing the best they can. So any way you can help them troubleshoot is good for all of us! 
