Trim/Extend using dimesions

[markh790572]

I used to be able to use dimension extension lines to trim/extend. Now when I choose a dimension I get the response "not a valid edge or selection method". Is there a setting or variable that I can change that will fix this?

[jpaulsen]

I don't recall ever trimming to a dimension. I just tried to trim to a dimension extension line and a dimension line in Civil 3D 2016 and received the same response.