How to fix broken subject line when sending proof
Recently, I came across a really interesting issue while sending a proof in Salesforce Marketing Cloud. We use an AMPScript variable as the subject line, which is passed from a personalization script.
When choosing the subject line prefix “[test email]”, we received an email that contained neither the prefix nor the personalized subject line. Instead, it showed broken personalization as =v(@subjectline)=%%.
The root cause is not know to me perhaps salesforce support can shed some light into this problem.
This occurs because when you use “[Test]” as a prefix and include AMPScript in the subject line, it can lead to unexpected rendering where the ending ‘]’ is mistaken for the closing tag of an AMPScript block.
I do not understand how that is possible, but let’s fix it and use the recommended way by using the proof subject prefix.
To fix this issue, we simply need to add a colon “:” after our “[test email]”. This will miraculously fix the problem. Also was advised to follow good practices for subject line and preheader of email template.
