The subject line alone may already answer the question with "It can't be done", but here's my problem anyhow:

I have a mail merge that is exported from Word as an attachment, but this means the BODY of the email in Outlook will be empty showing only the "subject" and the "attachment". I need a cover letter to go on each email. Being that my email list is to 4,000 subscribers/clients, it is not feasible to go into each individual email (putting Outlook on OFFLINE) to copy/paste the cover letter on each one.

I tried to "trick Outlook" by creating a signature that is for each "new email", but I guess mail merges aren't considered new emails because that trick didn't work (but it did for some reason work where I made read-receipt default).

Which leads me to, perhaps there's some way I can add a macro (or something.... ANYTHING....) that would put this cover letter in the body of each of the emails as they hit my Outlook outbox from the mail merge process? I'm also open to other ideas (I've already tried merging as an html, but that leads to formatting errors and the document itself is 10 pages long who wants to read that long of an email!).

Thanks for the help!