Halo 2A Not Working at all. (PC)

When Halo 2A Launched i was able to download and start the game fine, but after i got to the “Outskirts” mission, firstly before the mission even loaded I was hit with the error message something like “UE4 Error - Close game” “Fatal Error” all i could hit was “Ok”. Now whenever i try to start the mission im only hit with that error, the loading bar makes it all the way to the end but then it hits me with the error again. Halo: Reach, and CE work flawlessly.

you ever find a fix?