title: PHPPGAdmin on windows gives a `Virtual Class -- cannot instantiate` error
body: <p>I have PHPPGAdmin installed on windows 10.</p>
  <p>Postgres is fine and I can log into it on the command line.</p>
  <p>But when I try to log into PHPPGadmin web UI I get the following error:</p>
  <pre><code>Virtual Class -- cannot instantiate
  </code></pre>
  <p>Here is my PHPPGAdmin config file:</p>
  <pre><code>&lt;?php  
      $conf['servers'][0]['desc'] = 'PostgreSQL';
      $conf['servers'][0]['host'] = 'localhost';
      $conf['servers'][0]['port'] = 5432;
      $conf['servers'][0]['sslmode'] = 'allow';
      $conf['servers'][0]['defaultdb'] = 'template1';
      $conf['servers'][0]['pg_dump_path'] = 'C:/xampp/PostgreSQL/13/bin/pg_dump';
      $conf['servers'][0]['pg_dumpall_path'] = 'C:/xampp/PostgreSQL/13/bin/pg_dumpall';
      $conf['default_lang'] = 'auto';
      $conf['autocomplete'] = 'default on';
      $conf['extra_login_security'] = false;
      $conf['owned_only'] = false;
      $conf['show_comments'] = true;
      $conf['show_advanced'] = false;
      $conf['show_system'] = false;
      $conf['min_password_length'] = 1;
      $conf['left_width'] = 200;
      $conf['theme'] = 'default';
      $conf['show_oids'] = false;
      $conf['max_rows'] = 30;
      $conf['max_chars'] = 50;
      $conf['use_xhtml_strict'] = false;
      $conf['help_base'] = 'http://www.postgresql.org/docs/%s/interactive/';
      $conf['ajax_refresh'] = 3;
      $conf['plugins'] = array();
      $conf['version'] = 19;   
  ?&gt;
  </code></pre>
  <p>This is my <a href="https://pastebin.com/vwC4y9Sh" rel="nofollow noreferrer">phppgadmin config</a> with the comments.
  This is my <a href="https://pastebin.com/tQn74jNz" rel="nofollow noreferrer">apache config</a> in case these help.</p>
  <p>What am I doing wrong, and how do I correct it?</p>