How do I change the automatic line formatting in Word 2007?

[Loren]

In Word 2007, there is an automatic formatting applied when a series of
underline characters are entered. (i.e.
______________________________________).

When these characters are entered, Word automatically reformats it to a sort
of horizontal line. I like the line, because it essentially doesn't take up
any extra room, due to fitting between the lines. I have been using in many
of my documents, but I can't figure out if or how I can change it. I don't
even know what the function is called.

Anyone have any ideas? I appreciate the help!
Thanks

 

[Suzanne S. Barnhill]

It's a border. See http://word.mvps.org/FAQs/Formatting/CantGetRidOfLine.htm
and http://word.mvps.org/FAQs/TblsFldsFms/Borders.htm