Protecting all Google users from viruses, malware, and other abusive content is central to user cyber-safety and sometimes we remove access to certain files in order to provide these protections.

On Tuesday, October 31, we mistakenly blocked access to some of our users’ files, including Google Docs. This was due to a short-lived bug that incorrectly flagged some files as violating our terms of service (TOS). The blocking raised questions in the community and we would like to address those questions here.

The Google Docs and Drive products have unparalleled automatic, preventive security precautions in place to protect our users from malware, phishing and spam, using both static and dynamic antivirus techniques. Virus and malware scanning is an industry best practice that performs automated comparisons against known samples and indicators; the process does not involve human intervention.

Tuesday’s bug caused the Google Docs and Drive services to misinterpret the response from these protection systems and erroneously mark some files as TOS violations, thus causing access denials for users of those files. As soon as our teams identified the problem, we removed the bug and worked to restore access to all affected files.

We apologize to our users for any inconvenience this incident caused and remain committed to offering high-quality systems that keep their content safe while fully securing their files.