Final Draft 7 is not supported on Mac OS X 10.12 (Sierra), 10.11 (El Capitan), 10.10 (Yosemite), 10.9 (Mavericks), 10.8 (Mountain Lion) or 10.7 (Lion), it's too old. If you need to run Final Draft on a computer with one of these operating systems, you will want to upgrade to FD10, which is compatible with 10.12 / 10.11 / 10.10 / 10.9.
If you're on OS X 10.6.8 or older:
This issue can usually be resolved by repairing permissions.
Final Draft should now launch without any problems.
NOTE: All support for Final Draft 7 and older has been discontinued.