Are there any parameters in the Queries that don't appear. That is, if you
open the query in Access, does a dialog box pop up asking you for a
response?
In Word, from the Tools menu, select Options and then go to the General tab
and check the box against the "Confirm conversions at open" item. Then when
you attach the data source to the mail merge main document, try selecting
DDE as the method of connection when a dialog box opens that asks how the
connection should be made.

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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
> Word 2003 Mailmerge doesn't list all Access 2003 Queries as potential data
> sources. Most are listed in the Tools setup for data sources, but not all.
> The queries are basic Select Queries.
> Why would this happen?