Outlook Express is completely deprecated and Gmail took a lot of business from both Microsoft and (now) HCL.
From Microsoft's Support Site:
OutlookExpress: Move your email to Outlook.com. Microsoft doesn't make or support OutlookExpress anymore.
From Wikipedia (historical perspective):
Outlook Express, formerly known as Microsoft Internet Mail and News, is a discontinued email and news client included with Internet Explorer versions 3.0 through to 6.0. As such, it was bundled with several versions of Microsoft Windows, from Windows 98 to Windows Server 2003, and was available for Windows 3.x, Windows NT 3.51, Windows 95, Mac System 7, Mac OS 8, and Mac OS 9
Update the offerings for current mail programs or remove the installation selection sub-menu tree if you prefer business partner solutions. Keeping deprecated entries makes the product appear dated.