Hi,
By default, Word automatically creates six different types of border lines
that stretch across the page when you type a hyphen (-), the underscore
character (_), an equal sign (=), a tilde (~), the pound sign (#), or an
asterisk (*) three or more times at the beginning of a new line with nothing
before, between, or after these characters and then press Enter.
If you want to type one of these characters three or more times without
creating a line, simply type a space or some other text after them before you
press Enter. If you forget to insert a space or other text and a line
appears, you can remove it immediately by pressing Alt+Backspace or Ctrl+Z,
that is, either of the keyboard shortcuts that undo the previous action.
These lines are created as the lower border of the previous paragraph. You
can take advantage of this fact to remove such a line when undoing the
previous action can no longer remove it. In this case place your cursor
immediately above it, that is, within the previous paragraph and press
Ctrl+Q. Pressing this key resets the formatting of the paragraph to the
default formatting, which generally specifies no borders.
You can disable the automatic generation of these lines by performing the
following steps. In Word 2007, click the Microsoft Office Button, click Word
Options, click Proofreading, click Autocorrect Options, and then on the
AutoFormat As You Type tab clear the Border Lines check box. After you
disable this feature, you can enable it again by selecting the Border Lines
check box.
To disable this feature in Word 2003, on the Tools menu, click Autocorrect
Options. Then in the Autocorrect Options dialog box, on the AutoFormat As You
Type tab, clear the Border Lines check box, which is located in the Apply As
You Type Options section. After you disable this feature, you can enable it
again by selecting the Border Lines check box.
