A Clientnet adminsitrator has setup an administrator blocked/detected malware alert and is unable to see placeholder "Plain text section of the email body (%p)" in the email notification.
Some placeholders are available only for certain types of alerts. Others are available only when the alert is configured for Administrators.
This is particular placeholder for email alerts, only adds the plain text section of the email body, which contains no formating. This does not include any HTML tags as the email would no longer be plain text but HTML as this can contain formatting.
To protect confidentiality, this placeholder is not allowed in messages to administrators. See the following link to read more About placegolders in email alerts.