Using osx 10.12.6, AE v 14.2.1.34
I set everything up for a simple arm rig, create a controller, select everything in the proper order and when I go to click the check icon for 2+1 IK nothing happens.
I've re-installed a few times and even manually a few times and this function doesn't work.
IK not working
Re: IK not working
I think I was just in this boat, I hope this is the answer for your problem: viewtopic.php?f=16&t=52
Re: IK not working
Try to enable "Javascript Debugging" in the general preferences of After Effects too, it may give more clues to what's happenning