AutoCAD: No Fill on Polylines With Width

Note to self on the things to check when Polylines with width are unfilled:

• Check the current Visual Style. The 2D Wireframe Visual Style supports filled polylines; the Wireframe Visual Style does not. Other Visual Styles either do not support fill (such as Hidden or Sketchy), or will dim the fill (such as Shaded with Edges or Xray).
• Check your view direction. You will also need to know the plane in which the Polyline with width was drawn. For fill to display, the view direction needs to be perpendicular to the Polyline's plane. Set the current UCS so that the X-Y plane is the plane in which the Polyline was drawn, and then set the view direction to Top. Many times someone inadvertantly drags the View Cube ever so slightly away from "Top". It may be hard to tell from the View Cube or the drawing contents (no obvious forshortening), but if you look at the UCS icon, you will see an indication of the Z axis and if you look at the in-canvas controls at the upper left corner of the drawing canvas, the middle control will say Custom View instead of Top. Reset the view direction to Top.
• Check the setting of FILLMODE. If it is set to 0, reset it to 1. (To save keystrokes, you can also use the FILL command - turn fill On.) You will likely have to do a REGEN after changing the value to see the change on screen.