Why does a horizontal line always appear after adding a header and footer in WORD?

1. Open the task pane and select the "Styles and Formatting" task.

2. Double-click the title in the document, and a dotted rectangle box will appear in the title (indicating the selected state).

3. Click the triangle of "Style and Format-Title" drop-down list and select "Modify" to open the "Modify Style" window.

4. Select the border item from the format, and then select None in the border (or border and shading) window. Just press "OK".