I recently downladed the Autocad 2015 student package and started working on a project of mine. I have a polygon and want to bump out the faces by exactly the same value. I am using the Arc command end,end,radius to do this. I set one end at the vertices of the 2 sides and then set the adjacent corner / end. The command line ask for the radius and after I have input the radius dimension, I get the error message of "invalid 2D point". This occured originally while trying to do the last side. I went back and removed the "bump out" on all the sides came back to the one side that I could not do as my starting point and I still get the same error message.
Steve K