Can someone please tell me why I can't revolve this

what's wrong with it?

WhyCantRevolve.dwg

I read this in 'Help'

"You cannot revolve objects contained within a block. Polylines that have crossing or self-intersecting segments cannot be revolved."

Does my polyline have crossing or self-intersecting segments?

If you zoom in to the start/finish point of your shape, you can see that the polyline line is not closed, and the end point intersects the first segment on the polyline so it is self-intersecting.

If you make the start and end points coincident, then all should be well. To check this shape, the first thing I did was to use PEDIT, and it immediately told me that the polyline was open.

if you select your drawing and grab either the start point or the end point you can stretch it to the other. Make sure you have osnap on and its set for endpoint. Then you can revolve it.

The point of intersection is so small that I had to zoom in really close to see it and to be able trim it. Thanks guys!