title: Installing kernel headers packages missing error
body: <p>I am trying to install kernel-headers but getting this error</p>
  <blockquote>
  <p>E: Unable to locate package linux-headers-5.9.0-kali1-amd64</p>
  </blockquote>
  <blockquote>
  <p>E: Couldn't find any package by glob 'linux-headers-5.9.0-kali1-amd64'</p>
  </blockquote>
  <blockquote>
  <p>E: Couldn't find any package by regex 'linux-headers-5.9.0-kali1-amd64'</p>
  </blockquote>
  <p>I have updated and uncommented this line  in sources.list</p>
  <blockquote>
  <p>deb-src <a href="http://http.kali.org/kali" rel="nofollow noreferrer">http://http.kali.org/kali</a> kali-rolling main contrib non-free</p>
  </blockquote>
  <p>but errors thats can't locate <code>regex</code> or <code>glob</code>. what I am missing?</p>