If you add the Envelope to the document, you cannot prevent the extra page
being there. Actually, the envelope is inserted before the page that was
there in the first place.
As deleting the Next Page Section Break will screw up the page setup for the
Envelope, you can either tell Word to print Page 0 of the document in the
File Print dialog, or create a new template that represents the envelope
that you want to use and create your envelopes by creating new "documents"
from that template.
--
Please post any further questions or followup to the newsgroups for the
benefit of others who may be interested. Unsolicited questions forwarded
directly to me will only be answered on a paid consulting basis.
Hope this helps
Doug Robbins - Word MVP