For example if might be possible to block any MP3 attachments to email messages. Content control can be used to filter chain letters and Spam from your email traffic. The threat of harassment and resulting legal liability can be reduced by implementing email content control. This software can be configured to attach legal disclaimers to outbound email. Encrypt your sensitive email.
Most email systems can support digital certificates .
It is worth noting that you need to ensure that the email recipient is also using digital certificates to allow the mail to be decrypted. Finally, monitor the compliancy of your Corporate security policies. Following up on policy breaches will allow you to determine how successful the application and acceptance of the policies are, and allow you to fine tune them if required. A security policy not actively applied isn't worth the paper it's printed on. We've installed a firewall.