Microsoft on Thursday announced the completion of the transition that involved migrating 150 petabyes of email over the past six weeks, CNET reported.
In February, when it announced it would be shutting down Hotmail and moving the hundreds of millions of existing Hotmail.com users to Outlook.com, Microsoft said it had 60 million active Outlook.com accounts.
In announcing the finished transition, Microsoft also unveiled two new features for Outlook: SMTP (Simple Mail Transfer Protocol) Send, which will allow mail to be sent from different email addresses; and closer integration with the company's SkyDrive, allowing users insert files and pictures directly from the cloud storage service into their emails.
Microsoft said of the current 400 million Outlook.com users, 125 million are accessing their accounts from mobile devices.
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