Originally Posted by Stefan Blom

Assuming that you mean footer rather than footnote, do the following: Double-click the footer to activate the header/footer view. Place the insertion point in the first paragraph of the footer (for example, in the word "Title"). On the Header & Footer Tools Design tab, click the Page Border button (in the Page Background group) and then click the Borders tab of the dialog box. Make sure "Apply to" says "Paragraph." Select the color that you want and then click in the preview picture to add the new color. Click OK.