Hello,
Do you have activate the sidebar in options?
Otherwise check the forumhome-template.
Find:
HTML Code:
{vb:raw header}
{vb:raw navbar}
After that there must be a code like:
HTML Code:
<vb:if condition="$show['sidebar']">
<div id="content_container"<vb:if condition="$show['sidebarposition'] == 'left'"> class="contentright"</vb:if>>
<div id="content">
</vb:if>