To close the pop-over ad do any of the following:
1) click in the area surrounding the pop-over
2) click the "Close" link the the top right corner
3) press the "esc" key.
If it does not close, please check that you are using the current version of your Web browser.
Pop-over ads are set to show no more than once per day, if you continue to see the pop-over ad on every page check that you have cookies enabled in your browser preferences.