Microsoft Completes Hotmail-Outlook Transition

Moving millions of Hotmail users over to was a gargantuan task that involved migrating 150 petabytes of emails.

Last summer, Microsoft signaled that Hotmail's days were numbered when it previewed

On July 31, 2012, the software maker unveiled a webmail service that adhered to the streamlined look and feel that has come to define the company's software and cloud-based services suite, including Windows 8 and Office 365. Sporting an uncluttered interface and social media integration, was positioned as an upgraded, next-generation version of Hotmail.

The transition is complete, according to Microsoft. Group Program Manager Dick Craddock announced the milestone in a May 2 company blog post.

"Today, we're excited to announce that we've completed upgrading all Hotmail customers to," Craddock wrote.

Folding Hotmail into swelled the newer service's user base, Craddock said. "Coupled with the growing organic excitement for, this has pushed us to over 400 million active accounts, including 125 million that are accessing email, calendar and contacts on a mobile device using Exchange ActiveSync," he stated.

Moving data from the long-lived webmail service was a massive technical undertaking as well.

The "upgrade" entailed migrating 150 petabytes of email, a process that took six weeks, Craddock said. Downtime was not welcome. "Of course, this had to be done with a live site experience that was handling billions of transactions a day," he wrote.

With the Hotmail era behind it, Microsoft is looking forward. "With the upgrade complete, we've turned our energy and attention to future innovation and to making even better based on your feedback," stated Craddock.

One example of that future innovation is SMTP Send. The feature, which is available now, allows users to send emails from other accounts. Instead of appending "on behalf of" onto emails sent through another account—Gmail, for instance—via, recipients now only see the other account's address.

The capability can enhance privacy and anonymity, according to Craddock. "We knew this was a pain point for some people, and could be a real problem if you had a hidden alias, e.g., when Bruce Wayne wanted to send email as Batman. So now we've made it so that email sent from a different account goes through that account's SMTP server," he wrote.

Microsoft is also in the process of integrating and SkyDrive. Users will soon be able to insert pictures and attachments directly from their SkyDrive accounts with a single sign-on. SkyDrive integration should be available to all users worldwide within weeks, said the company.

The new features follow soon after Microsoft announced that it was enabling Skype calls directly from's Web-based interface. On April 29, the company launched a preview of a feature that allows the webmail service's users to place video and voice calls directly from their browsers. Microsoft is currently deploying the functionality to select users in the U.K. and the U.S.

Pedro Hernandez

Pedro Hernandez

Pedro Hernandez is a contributor to eWEEK and the IT Business Edge Network, the network for technology professionals. Previously, he served as a managing editor for the network of...