One of the world's most widely used email platforms serves hundreds of millions of active users across email, calendar, and task management, making it a high-value target for creating fake accounts to commit downstream fraud and extortion at scale.
Microsoft Outlook.com Reduces Fraud and Abuse by 98%
One of the world's most widely used email platforms serves hundreds of millions of active users across email, calendar, and task management, making it a high-value target for creating fake accounts to commit downstream fraud and extortion at scale.
33%
improvement in good customer throughput
98%
reduction in fraud and abuse
100+
languages supported globally
THE CHALLENGES
Large-scale fake account registrations used to send malicious and fraudulent emails, including extortion attempts targeting end users.
Legacy controls failed to stop bot-powered fake account creation, allowing abuse to continue at scale.
SMS verification — the fallback solution — was costly, easy for fraudsters to circumvent, and created friction for legitimate users.
Good customers were blocked or delayed due to VOIP numbers or area codes associated with fraudulent activity, damaging throughput rates.
THE ARKOSE TITAN SOLUTION
Arkose Titan was deployed across new account registration to differentiate between legitimate users, bots, and malicious humans in real time.
New users were presented with adaptive enforcement challenges when sending their first email, with custom rules triggering additional challenges when downstream abuse patterns were detected.
Incrementally complex challenges were presented to bad actors attempting to distribute malicious content, eroding the time and profitability of attacks.
Deployed globally across the full Outlook.com platform, with support for over 100 languages.
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It ultimately comes down to money and how much they can get out of an attack. We recognized that the cost of circumventing the Arkose Labs solution was prohibitively high, whereas the cost-benefit analysis was in the fraudsters' favor for alternative fraud controls.
BUSINESS RESULTS
33% improvement in good customer throughput following deployment.
98% reduction in fraud and abuse — malicious users blocked from carrying out large-scale attacks after account creation.
SMS verification costs eliminated, with each check costing significantly less than the prior approach.
Customer complaints about SMS verification stopped entirely, reducing burden on internal support teams.
Global rollout successfully completed across the full Outlook.com user base.
Block bad traffic. Welcome good humans and good agents.