Hello Antti,

It is unfortunate that you are in this situation. It seems that this iTunes/iPhone update is removing 32 bit core audio components that are needed by any 32 bit audio program attempting to connect your Mac's audio setup (this is not only Finale encountering this). This will prevent these programs from running and they will close on launch with a macOS error message. The best suggestion I can offer to get more details and a possible fix is to contact Apple directly about this.

As a quick work around, you can download the free trial of v26.  With this version, you can at least open any files that you need to work on immediately and make changes and save. This is a 64 bit program so it is not affected by the problem.

I prefer David’s solution. If Finale is the only app that is affected, updating to 26 is the best bet and far less hassle than any other solution.

You can reinstall the OS through the Repair Partition but the next time you hook up your iPhone, it will probably happen again. If you do reinstall Sierra, reset the clock in Terminal first as the certificate has expired for Sierra.

Nothing wrong with using an old Mac to run old apps. I have a G4 and am deciding which of 4 Macs I have to run a couple of 32 bit apps I still like. None of them are being used for current applications such as syncing a current iOS device.

It’s decision time.