How to remove continuous line? | Word 2007

When you have just created continuous line then you can click on the lighting button and undo the line. You can also stop it from doing that again in the future. The button will disappear when you have done some more actions afterwards.

The other option to use in this case is to put your text cursor right above the line and go to Home tab under Paragraph section. Under “Border” button choose “No Border”.