All my bulk emails from civiCRM bounce and the recipient is put on hold. The bounce report lists SYNTAX.
I brought this to the attention of my hosting company and they replied "please provide us with the full email headers of one of the bounce-back messages."
Trouble is I cannot locate a bounced email to provide the headers. Where are these located in civiCRM?
My civiCRM instance: civiCRM: 5.40.3; Drupal: 7.80