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Microsoft 365 400 million active accounts, Hotmail upgrade complete and more features on the way

When we launched the preview of, our goal was to build the best email service in the world, capable of scaling to over a billion active customers. When came out of preview, it was already the fastest growing email service thanks to your support. The last two months have seen the release of a new, modern calendar, a refreshed app for Android devices, two-factor authentication for your account, new international domains for people around the world, and the release of a preview of Skype calling in

Today, we’re excited to announce that we’ve completed upgrading all Hotmail customers to 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.  We’re also pleased to announce that we’re adding two new features to SMTP send, so it’s easier to send mail from different email addresses, and deeper integration with SkyDrive.

Completing the upgrade: migrating 150 petabytes of email in just 6 weeks

When came out of preview in February, it already had more than 60 million active accounts. However, Hotmail was still one of the most widely used services, with over 300 million active accounts. This made the magnitude of the process incredible, maybe even unprecedented. This meant communicating with hundreds of millions of people, upgrading all their mailboxes–equaling more than 150 million gigabytes of data–and making sure that every person’s mail, calendar, contacts, folders, and personal preferences were preserved in the upgrade. Of course, this had to be done with a live site experience that was handling billions of transactions a day.  With your help, we were able to do all of that in just about 6 weeks. We’ve spent the last few weeks ensuring that everything was completed in line with our high quality expectations.

We’ve been focused throughout the upgrade on ensuring that every customer has a great experience. We’ve been overwhelmed with the response so far, based on the comments we’ve received.  Here are just a few of the verbatim comments that were sent through the in-product feedback tool:

  • “Oh my goshwow!!! This is gorgeous! I didn’t see this coming – this is a very welcome experience. Thanks for the new!”
  • “This is awesome. I’d like to say these changes will definitely make me come back and delete my other accounts like google and yahoo! This is much smoother to navigate and transitioning between skydrive and mail is awesome. This is such a big improvement. I have not played with much of the features yet, but thank you thank you. Alias setup was painless and ease of use is bar none. I’d definitely recommend to my friends.”
  • “Wow!! The interface is perfect, modern and feels like Windows 8. I’m really enjoying the new UI approach from Microsoft.”

To underscore the differences between the two services, here’s a screenshot comparing Hotmail to You can instantly see the difference in the clean new look. The chrome is minimized so your content is front and center, information is organized so that you can easily see what’s most important, large display ads are gone and the entire visual aesthetic is designed to be fast and intuitive.

Hotmail inbox

BEFORE: The final look of inbox

AFTER: The modern look of

Of course, whenever a widely-used consumer service makes any substantial change, there will always be some folks that don’t like it, and that shows up in the feedback, too. It’s gratifying in a sense because it means those customers loved the previous set of changes we made. With a communication service that is constantly evolving, we try to strike the right balance between bringing out major improvements and keeping true to what our customers love. Our belief is that as people start using the new experience, they will come to love it even more than they loved Hotmail. We are keenly listening to what our customers have to say, and we’ll make the right set of adjustments to ensure that we make the experience as great as it can be. So to all those providing feedback: thank you and keep it coming. In addition, during the upgrade period we experienced a few service interruptions, and we’ve worked hard to respond quickly to each one. We know you rely on your email and for those who were impacted we apologize and appreciate your continued support.

Here are a few of the most common things we’ve heard about:

  • Do I have to change my email address? No, you will always be able to use your Hotmail address. No need to ever change,
  • Do I need to update settings on your phone or other apps? No, since you keep using your same email address, there is no need to change any settings on your devices.
  • What happens with Hotmail Plus? Your Hotmail Plus account will continue to work with, no need to make any changes. As before, your account never expires and you don’t see any ads.

You can find answers to other frequently asked questions and more on this page.

With the upgrade complete we’ve turned our energy and attention to future innovation and to making even better based on your feedback. You’ve seen a number of these updates over the past few weeks, and today, we’re starting to roll out a few more. We’ll be releasing the new SMTP send and SkyDrive integration gradually, so it may take a few weeks before everyone using sees those new features.

Easier to send messages from other email addresses: no more “on behalf of”

You’ve always been able to send and receive email from other accounts using your account. But, in the past, when you sent email from using a different email address (say, because you switched from Gmail and are still using that Gmail address when you reply to folks), the recipients would see the email being sent “on behalf of” that other account. For instance, this could look like this:

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. That way, the recipient just sees that account’s email address, like this:

This should work for any email provider that provides POP or IMAP access. If you want to take advantage of this feature, in the Options menu , click More mail settings, click Your email accounts, and then scroll down to the section titled Add an email account:

From there, you can add a send-only or a send-and-receive account, and we’ll configure the SMTP server settings as part of that. This new SMTP send capability will be available worldwide in the coming weeks.

Deeper SkyDrive integration: insert files and pictures directly from SkyDrive

There are a number of ways we’ve integrated and SkyDrive: a single Microsoft account for signing in, a shared contact list and set of connected networks, the ability to send large attachments, a shared header, and much more.  Today, we’re excited to release the direct integration of SkyDrive into the compose experience. When you’re sending an email message, you can select files from your SkyDrive and we’ll automatically turn those into the right thumbnails with links that have the right permissions tied to people that receive the email. When you insert pictures from SkyDrive, you automatically get a beautiful photo mail. And it’s easy to edit the message, and add or remove files and pictures right from the new message compose experience.  This new integration is starting to roll out today and will be available worldwide in the coming weeks.

Here’s what that will look like:


Thank you and more to come

We want to give a huge “Thank you” to all of you who have supported Hotmail over the years, for some of you, that’s going back as far as 1996.  It has been an amazing journey and we’ve been honored to provide you with a great mail experience for many years. When we launched the original preview of, we knew that we were committing to building the world’s best email with a brand and product experience that spans from consumers all the way to the largest organizations. We’re excited to have you join as we write the next chapter in modern email from Microsoft.

Thank you for all the feedback along the way and everything you did to help make the best and fastest growing personal email out there.  We’re excited to keep hearing from you and there’s a lot more to come.  Welcome to the new and onwards to a billion inboxes!

— Dick Craddock, Group Program Manager,

(This post was updated to clarify that the SMTP send capability would also be rolling out over a period of a few weeks.) 

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