How to Add a Horizontal Line in Word 2007
Microsoft Word 2007 allows you to quickly add horizontal lines in documents by using the Auto-format feature. This feature transforms certain characters into a horizontal line when you press the "Enter" key. Word 2007 offers six line styles to choose from by entering the appropriate combination of characters. For this feature to function, the default "border lines" configuration of Word must be maintained. If this feature is no longer enabled, you can reconfigure it to allow easy creation of horizontal lines.
Configuring Word 2007
Click the top, left "Office" button and click the "Word Options" button at the bottom of the drop-down menu.
Click "Proofing" on the left pane of "Word Options."
Click "AutoCorrect Options" at the of the right pane.
Click the "AutoFormat As You Type" tab of the "AutoCorrect" window.
Check "Border lines" in the "Apply as you type" section and click "OK" to close the "AutoCorrect" window. Click "OK" to close the "Word Options" window.
Adding Horizontal Lines
Type three dashes (---) on a separate line and press "Enter" to add a thin horizontal line.
Type three underscores (___) on a separate line and press "Enter" to add a thick horizontal line.
Type three equal signs (===) on a separate line and press "Enter" to add a thin, double horizontal line.
Type three pound signs (###) on a separate line and press "Enter" to add a triple horizontal line, in which the middle line is thicker than the top and bottom lines.
Type three tildes (~~~) on a separate line and press "Enter" to add a thin, wavy horizontal line.
Type three asterisks (***) on a separate line and press "Enter" to add a dotted horizontal line.