Attaching .pdf documents to email lists

Hi

I'm looking for a time saving way to send out emails to multiple people with the same (personalised) email text but with a different pdf attachment to each person.

I am trialing Kutools for Excel and have set up a mailing list but while everyone is getting the personalised email, nobody is getting the attachment.

Is the problem with trying to attach a pdf document.

Is there a better way?

Many Thanks