Google is expected soon to begin a gradual rollout of new security features in Gmail that warn users if the system could not authenticate the sender of an email message. Starting this week for browser-based users of Gmail and Android users, Google will display a question mark over a sender’s profile photo or user logo...

Google beefed up the way it displays Safe Browsing Alerts for Network Administrators this week, adding information about sites peddling unwanted and malicious software as well as those caught carrying out social engineering attacks. Google debuted the service, which notifies network admins after observing potentially damaging URLs on their networks, in 2010. Going forward, administrators...