How a simple HTML-inspired startup became the backbone of Microsoft's modern digital ecosystem
Born in 1996 as a scrappy webmail service named for its HTML roots, Hotmail was once the internet's largest inbox. After a $400 million acquisition by Microsoft, it endured security crises and identity shifts to eventually evolve into the robust, cloud-integrated Outlook.com platform that millions rely on today.
Founded by Sabeer Bhatia and Jack Smith, Hotmail launched on July 4, 1996, as one of the web's first email services. Its name was a clever nod to HTML, the language of the web, and it offered users the revolutionary freedom to access their mail from anywhere. Initially backed by $310,000 from Draper Associates, the service grew rapidly, boasting over 8.5 million subscribers by December 1997. Microsoft acquired the platform that same month for an estimated $400 million, integrating it into the MSN family.
The service's history is marked by significant technical and security hurdles. In 1997, a major incident caused data loss for 25% of its users. Later, in 2001, a simple URL-based vulnerability allowed unauthorized access to millions of accounts, an event described as the most widespread security incident in web history at the time. These challenges forced Microsoft to overhaul its infrastructure, moving from a mix of FreeBSD and Solaris toward a Windows-based environment, eventually transitioning to the Office 365-based architecture that powers Outlook.com today.
The transition to the Outlook brand was completed in May 2013, following a preview period that began in 2012. By May 2013, the service reached 400 million active users. Unlike its early days, modern Outlook.com emphasizes security and integration, featuring two-step verification, DMARC support, and seamless connectivity with OneDrive and Office web apps. While it has faced criticism regarding privacy—notably in 2014 when Microsoft accessed a private account during a trade secret investigation—the company has since committed to involving law enforcement for such matters, marking a significant shift in its operational policy.
Source: Outlook.com
