It looks you have a main table with 2 rows and 3 Cols. You have put another table in the bottom row.

This table which is basically your content pane and your solpartmenu is not correctly done.

This table is two rows and two cols. in the first row you have menu and content pane and in the second row you have the left pane that does not make sense? I have recreated the content table as a guide and given it some colour code for you to see what should be. It should be used as guid not as the final skin as I have put no breaking spaces in it for you to see they layout..

Salar
<table border=0 cellpadding=0 cellspacing=0 width=761 height="100%">
       <tr>
  <TD width=150 height=50% align="left" valign="top" bgcolor="#9966CC" style="padding-top: 10px"><dnn:SOLPARTMENU runat="server" id="dnnSOLPARTMENU" Display="vertical" separator='<img src="spacer.gif" width=1 border=0>' usearrows="false" userootbreadcrumbarrow="false" separatorcssclass="MenuSep" rootmenuitemactivecssclass="ParentSel" rootmenuitemselectedcssclass="ParentHover" rootmenuitemcssclass="ParentItem" />&nbsp;</TD>
  <TD  height="500" rowspan="2" align="left" valign="top" class="ContentPane" id="ContentPane" runat="server" visible="true">&nbsp;</TD>
  </tr>
<td width=150 height="500" align="left" valign="top" bgcolor="#FF6633" class="LeftPane" id="LeftPane" runat="server" visible="true">&nbsp;</td>
    </table>

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