$re = '/(?ms)^(?<message>.*?)\s*:[\r\n\s]+ProgID\s+:\s+(?<ProgID>[^\r\n]+)/m';
$str = 'Outlook a désactivé le ou les compléments suivants :
ProgID : ColleagueImport.ColleagueImportAddin
GUID : {EFEF7FDB-0CED-4FB6-B3BB-3C50D39F4120}
Nom : Microsoft SharePoint Server Colleague Import Add-in';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($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