A phishing campaign is targeting users of Outlook.com, potentially affecting the 400 million users who use the free email service, according to the cybersecurity firm Malwarebytes.
Users are warned that an email purporting to be from Microsoft is circulating that threatens to disable their account unless they verify it, with a link in the email putting the victim through to a website that steals their details.
The email reads: "Dear Microsoft User, Please note we have temporary blocked your account from receiving e-mails, because we detected fraudulent and spam, activities from your mail box to some blacklisted email address, So for your own safety verify your account. [sic]
"If a verification respond is not gotten from you in the next 24 hours, we are sorry we will be forced to permanently disable and delete your account from Microsoft Account."