We have a Mac guy here that is mostly knowledgeable with a Mac, not me, he might be able to help. But I suspect you need to do a "clean" reinstall of Finale. Finale is looking for something and not finding it for whatever reason. On my WIndows PC Finale 27 takes a bit longer to open than previous versions did so perhaps Mac is the same.

Ernie is correct. Uninstall Finale, by dragging the app to the trash. Then run the cleaning app to make sure you’ve gotten everything. Finally, download a clean copy of the installer from the website.

It probably started when I installed Clean My Mac 

That is quite possible, CMM can remove paths and important System files. Usually it's Adobe users who scream the loudest after running it, though. Clean my Mac is never, ever necessary. The macOS is very good at healing itself and on those rare occasions when it isn't, CMM is never the solution — not once, not ever.

Back to your issue. You can remove and reinstall which may work or not. Reboot. Start Finale and wait for it to come up. If it crashes, start again. If it won't attempt to restart after a crash, reboot and try again. Once it is up, you should be good — at least till you run CMM again which I recommend you never do again.

If that works and I expect it will, it's because Finale is rebuilding all of your System paths and re-scanning all of your plug-ins. This can take a long time. 

Do you have NotePerformer by any chance? If so, this will happen with every NP update or reinstall. It was Arne Wallander who helped me diagnose how Finale handles plug-ins a number of years ago—surprised him, too. I forwarded that all to MM Support. This may have been 5 years ago.

Hi!

Thanks for your answers! I consider to install it from the scratch. And yes, I think CMM is the reason, because it started after I installed and used it. 

Br. Petri

Sometimes, I forget the obvious. If you have not yet reinstalled Finale, try this first. You are exhibiting one of the classic symptoms of corrupted Launch Services and yes, CMM can cause this. The symptoms are

Mac or any App takes too long to launch

Mac or any App takes too long to quit — or only quits if forced 

Otherwise, after you have Finale up and running you should quit all applications and reset the Launch Services. I discovered this when an Apple Security update crashed by not letting my Mac shut down about 10 years ago — oops! This resets the Launch Services for all Applications and your Mac to factory Default. It looks scary but is absolutely safe. Copy and paste each line into Terminal and you'll be ok.

How to Reset Launch Services to Default

1.Open Terminal and run these commands:

2.  /System/Library/Frameworks/CoreServices.framework/Frameworks/LaunchServices.framework/Support/lsregister -kill -seed -lint -r -f -v -dump -domain local -domain system -domain user -domain network   <Enter or Return key>

3.  killall Dock         <Enter or Return key>

4.  mdutil -E /        <Enter or Return key>   

5.Restart your Mac

This takes about 30 seconds on my M2 Studio but it can take a few minutes if many apps need to be repaired.

There are utilities that contain similar routines but I can't recommend any of them. Some only set it for your apps but not the Mac while others do the opposite. The above Terminal Command set is the only one I know that does both. I try to run it once a year or so as normal maintenance nowadays.

My best advice: avoid anything that claims to "clean" your Mac's SSD. There are many such utilities and they can really screw things up.