FCP7 won't migrate to new Macbook Pro
I am running FCP7 on a Macbook Pro on OS 10.10.5 Yosemite. Recently my Macbook GPU died, so I swapped my hard drive into a new machine. All of my programs and preferences and settings seem to have migrated fine EXCEPT FCP. When i try to open it, I get a prompt for serial #. I put in the serial # and get "Error 777." I don't have the original discs so can't do a re-install, just wrote down the serial.
I am just trying to get the program open so I can convert the project files to XML and open them in Premiere.
Any tips?
Final Cut Pro 7, OS X Yosemite (10.10.5)