The barcode produced by Word is POSTNET.
The USPS no longer accepts that format for bulk mail discounts -- see
http://support.microsoft.com/kb/897290. You might as well not use the
barcode feature at all. However, try putting the field in a borderless
table cell.

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Graham Mayor - Word MVP
My web site www.gmayor.com
Word MVP web site http://word.mvps.org
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> In Word 2003, selecting Postal Bar Code under Write Your Letter in
> Mail Merge correctly creates the field and the barcode prints
> correctly in horizontal text; however, it does not display or print
> in text rotated 90 degrees. The field is being populated from an
> Access query. Thanks.