Upgraded Ubuntu from 14.04 LTS to 16.04 LTS and Bugzilla stopped working
<p>I just upgraded my Ubuntu server from 14.04 LTS to 16.04 LTS. Upgrading the OS to a major new release always makes me nervous. Of course something had to break... bugzilla stopped working. I got the following output from my web browser:</p>

<blockquote>
  <p>Internal Server Error</p>
  
  <p>The server encountered an internal error or misconfiguration and was unable to complete your request.</p>
  
  <p>Please contact the server administrator at webmaster@localhost to inform them of the time this error occurred, and the actions you
  performed just before this error.</p>
  
  <p>More information about this error may be available in the server error log.</p>
</blockquote>

<p>Looking at the /var/log/apache2/error.log I saw the following:</p>

<blockquote>
  <p>AH01215: /usr/bin/perl: symbol lookup error:
  lib/i686-linux-gnu-thread-multi-64int/auto/List/Util/Util.so:
  undefined symbol: Perl_xs_apiversion_bootcheck:
  /var/www/htmls/bugzilla/index.cgi</p>
</blockquote>

<p>I spent hours searching the web for a solution.  <strong>No luck.</strong></p>