$re = '~\b\d{1,2}/\d{1,2}/\d{4}\s\d{1,2}:\d{2}:\d{2}\s?[AP]M\b~';
$str = '\\\\SomeServer\\HTTP\\demo1\\index.cfm 4 KB CFM File 2/19/2019 3:48:21 PM 2/19/2019 1:05:53 PM 2/19/2019 1:05:53 PM 5';
preg_match($re, $str, $matches, PREG_OFFSET_CAPTURE, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php