Third-party application called ‘Error Check System’ sends messages to Facebook users saying they have a problem with their profiles. Application sends them a warning that they have violated Facebook’s terms of service. Application is being used to collect information about users’ privacy from their profiles and send them a message to Facebook saying they are under investigation for violating the terms of Facebook’s Terms of Service. The application is a toolkit for Windows users to use to check their profiles for information about what they have done to make sure they are not violating the rules.”]
Source: https://grahamcluley.com/reported-facebook-violating-terms-service/