The file is likely broken.
Are you able to play games for the given week? Sometimes if you try to play the game, the game will freeze while trying to load up.
Sometimes...if you try simulating a few times, it will work.
I am currently slowly editing a franchise file, and I cant simulate the entire season and sometimes have to sim game by game. However, after the first season, it seems to work normally. I think the first season might be affected by the ratings being a bit off because of the editor. However, in the offseason, player ratings are recalculated in the game and corrected.
There are people better suited to answer your question than me, but from my experiences, thats what I can tell you.