Some customers are experiencing an issue where their opens and click through reporting are not updating properly. We are working to fix this as soon as possible.
You can not attach anything to a Constant Contact email. An alternative is to post the attachment to your website, and than put a link you your email to the file you want attached.
You cannot add attachments to a Constant Contact email. You can however, host the pdf on your website and put a link in your email to download the pdf.