
In Marketing Cloud Email Studio, is there something I need to do to set up the pre-header to display correctly? I am testing an email in which I entered pre-header text, but when I send the test, the preheader only displays as %%PreHeader%%. See email-preheader.png. There is a dropdown next to the preheader area in the email that says that AMPscript variables must be assigned a value. I assume that I'm assigning a value when I type in the preheader text in the text box. Please advise on how to get the preheader to display in the test email.
I know this is a few years late but in case anyone else runs into this issue, be sure you have a contact selected in your data extension (either the one you plan to send to or a test extension).
The pre-header and links like View on the Web and Preference Center won’t display properly in your preview/tests without a contact assigned.