[Louis Galdieri]

Are you sure that you’ve really removed FCP Studio? There are lots of hidden files. That’s the only thing I can think of doing, except a clean reinstall of the whole machine, but that will take a long time.

I wonder when Apple going to come up with a patch or fix or at least some support for this problem?

[Louis Galdieri]

I had this very same problem this morning: all of the sudden, I started getting the KGCore Plugin error message.

Final Cut wouldn’t open at all, so there wasn’t any question of cutting and pasting to a new project to try to work around the problem — and I’m not sure that would solve the problem anyway.

I spoke with Apple, and searched around, and it seems that the only way to solve the problem is to do a clean re-install of Final Cut Studio.

Before doing so, make sure you remove Final Cut Studio. Also follow the instructions for removing Compressor and related files at https://support.apple.com/kb/TS1888?viewlocale=en_US

Then reinstall Final Cut Studio. You will lose your settings and preferences, but the good news is you will be able to work again.

Good luck!