Yes. Users of cloud-hosted Office 365 may benefit from Microsoft's massive security efforts, including integrated antivirus, anti-spam, and anti-malware as standard. Office 365 data is stored in Microsoft's worldwide data centers, where specialized threat management teams foresee, detect, and neutralize unwanted access 24 hours a day, seven days a week. All messages are checked using Exchange Online Protection (EOP), and e-mail is protected with SSL/TLS both at rest and in transit.