I have a part that claims to have external references even though it clearly does not. It resists all attempts to resolve the issue. The problem originally presented itself as a feature with the -> indicator on it, but there was nothing in the feature definition that referenced other geometry. It was a simple Cut-Extrude with Through All as the end condition.
I have isolated the problem to the sketch that created the feature, even though the sketch does not have the -> indicator on it. If I delete the sketch, the external reference listed in 'File....Find References' goes away. Nothing other than deleting the sketch will work.
I have deleted all relations.
I have deleted all sketch geometry.
I have deleted all features in the model leaving only the sketch.
Nothing short of deleting the sketch works.
The only clue I have to what is going on is that when I delete the sketch (which now has no geometry in it), I see this:
Note the 'Align Group' dependent items. What the heck is an AlignGroup?