2013 I uninstalled AutoCAD Architecture 2013 and now i can't Install it again (software problems)

I uninstalled AutoCAD Architecture 2013 and now i can't Install it again, it appears as if the software is still installed so the new installation is bloqued "already installed" message).

How can i install the software again?

I tried using a regcleaner to erase all registers and folders but still nothing.

I tried manually erasing some still leftovers and still won't let me install (same "already installed" message)

Do i have to erase any particular folder o registry?

Please any help would be greatly appreciated.