Tested with phpBB version 2.0.17
1.Index page:
Open index_body.tpl
Find <!-- END switch_user_logged_out -->
After add the following code:
<table width="100%" border="0" cellpadding="10">
<tr>
<td><div align="center">
Place your Google 728*90 Ad Code Here
</div></td>
</tr>
</table>
2.Forum pages:
Open viewforum_body.tpl
Find </form>
After add the following code:
<table width="100%" border="0" cellpadding="10">
<tr>
<td><div align="center">
Place your Google 728*90 Ad Code Here
</div></td>
</tr>
</table>
3.Posts:
Open viewtopic_body.tpl
Find
<tr align="center">
<td class="catBottom" colspan="2" height="28"><table cellspacing="0" cellpadding="0" border="0">
<tr><form method="post" action="{S_POST_DAYS_ACTION}">
<td align="center"><span class="gensmall">{L_DISPLAY_POSTS}: {S_SELECT_POST_DAYS} {S_SELECT_POST_ORDER} <input type="submit" value="{L_GO}" class="liteoption" name="submit" /></span></td>
</form></tr>
</table></td>
</tr>
</table>
After add the following code:
<table width="100%" border="0" cellpadding="10">
<tr>
<td><div align="center">
Place your Google 728*90 Ad Code Here
</div></td>
</tr>
</table>