Image Number 3 for United States Patent #7979691.
A network is protected from e-mail viruses through the use of a sacrificial server. Any executable program or other suspicious parts of incoming e-mail messages are forwarded to a sacrificial server, where they are converted to non-executable format such as Adobe Acrobat PDF and sent to the recipient. The sacrificial server is then checked for virus activity. After the execution is completed, the sacrificial server is rebooted.