You can enter a game without all of your league files

Had computer issues today...... had to reformat My C: drive. got over it, got on league with 4 friends. We Queue up (normals, blind pick) and lock in. except when the game tries to launch, i get informed that I'm missing a file, and that i have to redownload league, since the repair tool failed. Can that kind of thing please be checked before i Queue up, because i probably got a decent leave buster for that. (for those interested, my friends won. the enemy mid afked after level 8, and they won 4v4).