title: Windows IIS - PHP PDO Mysql Could not find driver
body: <p>I have the following code to connect to a Mysql database from my local PHP (Windows, using IIS),</p>
  
  <pre><code>$dbhost     = "xxxx.database.windows.net";
  $dbname     = "yyyy";
  $dbuser     = "uuuu";
  $dbpass     = "pppp";
  $driver     = "sqlsrv";
  $connection = new PDO("$driver:host=$dbhost;dbname=$dbname",$dbuser,$dbpass);
  </code></pre>
  
  <p>php info says this:</p>
  
  <pre><code>Loaded Configuration File   C:\Program Files (x86)\IIS Express\PHP\v5.6\php.ini
  </code></pre>
  
  <p>I have the following in this php.ini file</p>
  
  <pre><code>[WebPIChanges]
  error_log=C:\Windows\temp\PHP56ForIISExpress_errors.log
  upload_tmp_dir=C:\Windows\temp
  session.save_path=C:\Windows\temp
  cgi.force_redirect=0
  cgi.fix_pathinfo=1
  fastcgi.impersonate=1
  fastcgi.logging=0
  max_execution_time=300
  date.timezone=Europe/Minsk
  extension_dir="C:\Program Files (x86)\iis express\PHP\v5.6\ext\"
  
  [ExtensionList]
  extension=php_mysql.dll
  extension=php_mysqli.dll
  extension=php_mbstring.dll
  extension=php_gd2.dll
  extension=php_gettext.dll
  extension=php_curl.dll
  extension=php_exif.dll
  extension=php_xmlrpc.dll
  extension=php_openssl.dll
  extension=php_soap.dll
  extension=php_pdo_mysql.dll
  extension=php_pdo_sqlite.dll
  extension=php_imap.dll
  extension=php_tidy.dll
  extension=php_sqlsrv.dll
  </code></pre>
  
  <p>This file exists: C:\Program Files (x86)\IIS Express\PHP\v5.6\ext\php_pdo_mysql.dll</p>
  
  <p>Why do I get a "could not find driver" error? My application pool can run 32-bit or 64-bit.</p>