New ways we're fighting spam in Hotmail

New ways we're fighting spam in Hotmail

  • Comments 15
  • Likes

Hotmail's fight against spam has certainly come a long way in the last five years. Over the last several years we've made substantial investments in the research and development of sophisticated anti-spam technologies. SmartScreen is the collective name we use for a cloud-based set of technologies and algorithms that leverage machine learning and artificial intelligence to assign a “spam probability” score to each incoming message. This enables us to filter out over 98% of the spam sent to Hotmail inboxes, blocking 5.5 billion spam messages per day.  Microsoft utilizes SmartScreen across Hotmail, Microsoft Exchange, and Microsoft Forefront, bringing consumers the benefit of business-grade spam protection on Hotmail.

With the soon-to-be-released new version of Hotmail, we’ve added a number of innovative new spam fighting technologies that will further reduce the amount of spam in your Hotmail inbox. Here's a short video featuring myself, Dick Craddock, and John Scarrow telling you a bit about how Hotmail's latest innovations help bring you the best spam fighting on the web.


New spam-fighting innovations include:

  • More advanced IP and content filtering – Hotmail receives over 8 billion messages per day, giving us 8 billion input variables to work with and learn from. Each message we receive further informs SmartScreen’s IP filtering algorithms, making SmartScreen even “smarter.” Because Hotmail is the largest webmail service in the world, it also receives more telemetry on bad IPs than most any other service – either directly or through third parties. This gives our spam filters more opportunity to inform their artificial intelligence than pretty much any other service.
  • Spammer infrastructure detection and destruction – SmartScreen not only blocks spam, it uses “x-ray vision” to see behind the URLs contained in malicious email to the source URLs, which we can then block along with their IPs. This means spammers have to abandon their current infrastructure and pay for new places to hide out. By making it more expensive to continue their business, we are taking away their economic incentive.
  • Time-traveling filters – We can't always identify a new spammer the moment they start sending spam. But once we identify one, we can go back and clean out spam that they’ve already sent to your inbox before you ever see it. We call this a time-traveling filter, because in some sense we are able to go back in time and get rid of the spam even after it's been delivered!
  • Personalized spam filtering – One person’s junk mail is another’s desired piece of mail.  Using artificial intelligence, Hotmail personalizes spam filtering according to the individual preferences of each of the 360+ million customers who use Hotmail, reducing false positives while improving effectiveness at the same time.
  • Tagging – Hotmail tags each message you receive, whether in your inbox or in the Junk folder, to help you understand little bit more about why the message was categorized as it was. For example, if you previously marked messages from a sender as junk, we'll tell you that, or if you use a client email program with Hotmail, we'll tell you when that program has rules that result in moving a particular message to another folder. This gives you more direct control of spam management in your inbox unlike any other service.

Krish Vitaldevara
Senior Program Manager, Windows Live Hotmail

Hotmail’s latest innovations in fighting spam
You must be logged in to comment. Sign in or Join Now
  • asher64
    1 Posts

    It appears that because of or despite all off your security, I can no longer send emails to my friends who have Hotmail accounts, and judging by what I have found on an internet search this problem has been going on for years.  Is this your way of trying to make sure we all use Hotmail to communitate with each other?  And before anyone says anything about my IP address being at fault, I have renewed it four times, and it still bounces back the the same "5.1.0 - Unknown address error 550-'SC-002 Mail rejected by Windows Live Hotmail for policy reasons. The mail server IP connecting to Windows Live Hotmail has exhibited namespace mining behavior." error. From what I can gather this has been reported to you several times and yet nothing has been done about it.  Fighting spammers is one thing, but stopping legitimate email users from contacting Hotmail users because you have blocked the ISP is beyond belief. Surely in this age of technology you must have found a more reliable way to sort out this issue. Will you please sort your policies out !

  • Quikboy
    30 Posts

    Great job Hotmail. Now maybe if some of y'all could help the Spaces team with their much worse spam issues...

  • x.iso
    1 Posts

    yeah, lately I'm getting more and more spam invitations in windows live network. that where spam filters need to be placed.

  • Great work. I get zero spam in my Hotmail. However, it would also be nice if you could somehow block strangers from inviting me to join their network on Windows Live so I can see them in their undies - I get atleast 3-4 such invites a week.

  • Sounds good. Let's see it in action.

  • @Chris-Gonzales : check this out

  • Deioneus
    12 Posts

    @Krish: Do you know when will Hotmail's automatic vacation responder be turned back on?

  • @DarrenG we are making significant investments to reduce abuse that originates from our network as well. In one of the future blogs we will focus on our efforts in this area and how users like you can help

  • DarrenG
    1 Posts

    What about outbound spam?  I'm receiving 3-4 phishing attacks per day per account sent through Hotmail.

  • This sounds good. For the past week I've been getting e-mails from someone who keeps placing the title in the middle and I block the sender but somehow it keeps coming back. Hopefully this will fix it

    will you guys go what Yahoo does and allow a pay per year feature to remove ads and get even more storage? That would be nice

  • @Drazick, we have exclusive inbox setting that allows only mail from contacts and safelisted entries to be delivered to the inbox while letting the user triage other mail before allowing it in. This serves similar purpose as a challenge & response system.

    @someone, when you access a Hotmail account via POP3 or Deltasync you get all the benefits of spam filtering we do because the mail has been received and processed by our MTAs. But at times, some client side filters override our spam verdicts with theirs, resutling in a different experience from Web. You can avoid this by turning off client side filtering in clients that support it it. Also, tagging would indicate if the destination of a message has been altered by the client.

  • 7flavor
    352 Posts

    How about fighting ads while using email? See this image: I can't do simple things like Sign out, swtich linked Hotmail accounts, Change hotmail options, Use web messenger or view emails in full view without accidentally clicking on a floating flash ad? Do you still refuse to acknowledge the problem?

  • someone
    156 Posts

    When I access Hotmail via POP3 or DeltaSync, do all of the spam filtering technologies of Hotmail work or only that of the email client?

  • Drazick
    16 Posts

    Why won't you let the user activate something like "Challenge & Response" filtering for non contacts mails?

  • I was Ok with mark as phishing scam, by doing this it enables me not to receive emails from the sender.