It may be the beginning of spring, but it might be easier to answer with a screenshot posted here; preferably with it selected, if applicable.
Choose the artboard tool, then from the tool options bar at the top open the Advanced options. These are all just additional auxiliary overlays that can be turned off there.
Hi Mylenium where abouts is the artboard tool located exactly?
I had the same problem. I was able to resolve it by resetting my Illustrator settings.
To reset Illustrator's settings. First, quit Illustrator. Then,
For a Mac, launch it while holding down Shift-Option-Command (Mac). This will call up a dialog asking if you want to delete Illustrator's settings. Hit "OK."
For a PC, go to where you would normally open illustrator, hold down Shift-Alt-Control, right click and select to open. This should reset all of the settings so that next time you create a new document, there shouldn't be a little green box. Also remeber to set you color mode back to RGB in the advanced settings when you create a new doc, if you are designing for the web.