title: Ubuntu : dpkg --add-architecture i386 throwing error --add-architecture unknown option
body: <p>I want to enable extra architecture (of 32-bit) in my 64 bit machine . I did <em>dpkg --print-architecture</em> to know the already known architecture i.e.amd64 . After that I did <em>dpkg --print--foreign-architectures</em> and got the result as i386(I want to enable this) . But when i typed <em>dpkg --add-architecture i386</em> , it is throwing an error saying that unknown option -add-architecture ? Please suggest some solutions for this . </p>
  
  <p>I refer this link by the way : <a href="https://wiki.debian.org/Multiarch/HOWTO" rel="nofollow">https://wiki.debian.org/Multiarch/HOWTO</a></p>