In order for e-mails to be scanned by the avast! Mail Shield, it is necessary that encryption is turned off in the mail client software. If encryption is required, the appropriate e-mail accounts need to be configured in the Mail Shield to establish a secure connection with the mail server. This will enable all incoming and outgoing e-mails to be scanned by the Mail Shield. All other e-mail accounts using unencrypted connections should be listed as unencrypted in the SSL Accounts settings of the Mail Shield (i.e. SSL/TLS encryption set to ‘None’, ports for SMTP to ’25′, for POP3 to ’110′ or for IMAP to ’143′, by default).