Ad Code being shown outside of a table (help!)

[Citizen]

<table>
<tr><td>
Hello World
</td><td>
YPN AD code Goes Here
</td></tr></table>

For some reason, the ad is displayed outside of the table. Any ideas?

[Ferrarislave]

Check to see if all your tags on the ad are closed. Also check the size of the ad and check to see if the cell has a fixed width and height....