Does the bottom border show up in Print
Preview? Some printers will not print the full page, to include the border if it is too close to the papers edge. If you adjust the border to be further away from the pages edge, it should print. Instead of applying a page border, you may have to draw a border using a rectangle shape and apply the desired line style.
You can also try to adjust the border margin to measure from "edge of page" instead of measure from "text". This setting is on the options button located on the page border tab under the Borders and Shading window. This may allow you to adjust the margin enough to be able to print the border.