Assuming that the sender is composing their emails in Outlook in an RTF Format (which is the default format setting for MS Outlook). This will necessitate that the recipients own email clients to be configured to both receive and view the email using this formatting. If they are not? Or are using alternate email programs? Then the e-mails will be not be shown properly and the viewing of any attachments will not be shown either.
We would therefore suggest that the sender should either format their e-mails in an alternate format i.e. RTF / Rich Text. Or that the recipient use the MS Outlook program to read these e-mails.