new license key

I'm having a few issues. My boss let me borrow FCP Studio 2 to install on my comp with their license key until I could get my own. Well, before I got my own, I had a scratch disk problem and I deleted FCP from my comp. Now I have purchased my own set of FCP Studio 2 and have installed, but it's bringing up the old licensing key. I can't put in a new one because FCP won't open up on my macbook. It will get to the loading screen because the scratch disk thing popped up and I selected a new location. After it does the loading screen, it automatically closes.

I have NOOO idea what to do next.

Someone please help!!