So we've sent out a html email to a large audience. HTML only. Text-only version was not edited to reflect the html version. Text-only version was NOT ticked to go out. Confirmed on the the approved email that was sent. Text Only = No
Gone to link performance and saw an odd link being clicked many times. It's a mailto: link, which is present in the plain-text. Again, did not tick in the settings for this to go out. But, looks to be that a large number of recipients received and clicked the link.
Is there a setting or bug that would cause the text-only email to go out, besides us not selecting that option?
By default, Marketo sends out both email versions (HTML and Text) to people, and they can view the email in either format! Email clients have the option to allow users to read email messages in plain text instead of HTML versions! And, in your case, recipients may have chosen to view and click the text version of the email, hence you're seeing the click events for the link in the text version of the email. For this reason, I'd always advise to review both the HTML and text versions of emails. FYR, when you check-mark the Text Only option in the Email Settings, Marketo will only send the text-only version of the email.
I hope this is helpful! Please let us know if you have questions.
This would also be in theory a positive outcome if it proved that some people’s mail clients are set to prefer the text part of a multipart email.
However, in practice it was probably automated mail scanners, not people, clicking the mailto: link, unless you also have proof that some of them sent an inbound email.