Extrude problem, not a meaningful result

Hello world. CAD for a long time, new to Inventor. I have tried over and over to produce this extrusion but keep getting the the same error that "errors occurred during update", "could not build this extrusion" and "attempted operation did not produce meaningful result".

I think this is something akin to problems in CAD where you don't have a closed polyline or region when trying to extrude into a solid, or maybe like a self-intersecting polyline that won't extrude. I'm not sure how to look for problems like that though, would someone be so kind as to take a look and see what they can see? This is an example from a textbook but it's me learning on my own for work, not related to school. Thank you kindly in advance.

HANGER JAW.ipt

There are redundant points (at the origin). If I had to guess I'd suggest possibly the 2.5" dia. radius could be the culprit depending on how the sketch was drawn.

Anyway, to fix just right click anywhere in the browser when you're in edit sketch mode and select sketch doctor from the drop down menu. Follow the prompts to diagnose sketch which will find the redundant points and ask you if you'd like to combine them. Yes you would, and as a good double check re-launch sketch doctor when you're done and hit diagnose sketch again. Should get a "no problems" result.

Thank you much, started with the Sketch Dr. (which I didn't know about), then redid some constraints that seemed like they could have been replaced by a better set of them and voila. Thanks ConMan.