Something similar has happened to me today... my computer started verifying files over and over again without running the game itself.
First, I must say I decided to stop updating a few months ago and I had been working on my own squads for the new season (they are lost now, which makes my blood boil). However, today Origin forced me to repair the game and install the updates or otherwise I would not be able to run the game (a pop-up window stated such a thing...). I finally could repair this issue, but now I have a second problem: every time I try to load mods using Fifa Mod Manager it will not work!
The error message is the following: "InvalidOperationException; sequence contains no matching element".
I have tried reinstalling the game and Mod Manager, but although the game now runs properly, it still fails to load mods. Does anyone know what may be going on here?