Most email clients can display HTML (sometimes called 'rich text') messages. When you send an HTML message, Act-On also automatically includes a text-only version that can be displayed by older email programs. A message in this two-in-one format is commonly called a multipart message.
To create an email that includes only a text version without any HTML, click Outbound > New Message and select the option for Plain Text Message. Please note that message opens cannot be tracked in text-only emails.
You can then write or paste your message copy in the Design tab of the email editor.