You only return the runners who were put out as they were the ones placed in jeopardy. If a runner advances safely, you allow that advance as the defense should be making a play based on their actions whether the IF was called or not.

Now I'm confused
 

This was hinted at in this thread, but I'm not clear on it...If a popup, meeting all the requiremnts of IF rule, is cleanly missed by the fielder and settles foul, is it still an IF? Or does 'IF, if fair' refer to a ball whose trajectory would cause it to be touched or caught in foul territory?

Re: Now I'm confused
 

Cannot tell you with the information you provided. Is it a fair or foul ball?

Rule specifically states it must be a fair ball to be an IFF.

IFF rule-ad naseum
 

(I tried posting this earlier but it didn't show...sorry if it appears twice then).

Batter has 1 ball, one strike; 1 out, runners on 1st and 2nd. Batter hits popup whose trajectory from vantage point of PU indicates ball will land 2-3 feet inside line and well short of 3B bag. PU yells "IFF". Fielder waits under ball, which she then cleanly misses. Ball drops at her feet, rolls across the line and settles foul. Is it a foul ball and the batter gets to continue batting? Or is it an infield fly since all the conditions were met (especially since the fielder had a chance to catch the ball with normal effort)? Is the batter out? Thanks in advance from an obvious 'non-ump'.

Re: IFF rule-ad naseum
 

All of the conditions were NOT met, even though it seemed like they would be when the umpire made the call.

ASA Rule 1 - DEFINITIONS - INFIELD FLY starts out this way,The rule ends this way...FOUL BALL, dead ball, runners return, batter returns to the box (exception SP with 2 strikes - batter out on strike 3).