Why can't I personalize certain sections of my syndicated mailing?

Suppliers make the decision regarding what emails/campaigns and what sections of the emails/campaigns can or cannot be edited. If you do not see the dotted-line surrounding the section of the campaign you wish to edit it means that you cannot edit that particular section of the campaign.

If you still wish to edit a campaign template that has been locked down by the supplier, you can export the raw HTML of the template and use Create Your Own Campaign feature.