I'm using version 15.04.
I tried looking at the object through the different modes - especially the layers mode - and it only shows the new object I want to print, but still prints the previous object.
I usually print one object at a time and deleting the object and loading a new one doesn't work - still prints last object printed. I remember there's a "clear platform" selection from the drop down menu. I'll check that out later and see.
Otherwise, I'll try re-installing the software and see what happens. Thanks for the reply, though.