You have not followed the instructions in the Preparations part of the
article. Specifically, you have not set the reference to the Outlook Object
Library.
You must follow the instructions excatly to the letter, otherwise it will
not work.
I am not sure what you mean by "create a merge field in the subject line of
an email mail merge"
But if you want a different subject line for each message based on the
content of a mergefield in the datasource, you should include that
mergefield in the catalog (or directory) mail merge that is created as part
of the process and retrieve the contents of that field in the same way as
the contents of the other fields are retrieved.
--
Hope this helps.
Please reply to the newsgroup unless you wish to avail yourself of my
services on a paid consulting basis.
Doug Robbins - Word MVP