Outlook Express is an e-mail/news client that was included with several versions of Microsoft Windows, starting with Windows 98 through the release of Windows XP. Outlook Express was also bundled with Internet Explorer 4.0, and available for Windows 95 and Mac OS 9. In Windows Vista, Outlook Express is replaced with Windows Mail. Windows Live Mail has since been released as the successor to Outlook Express and Windows Mail. Microsoft Entourage, sold as part of Microsoft Office for Macintosh, has replaced the Macintosh version.