Problems in Alignment and table box not closing

https://www.flickr.com/photos/63296411@N08/16162493480/in/photostream/

I added a new section but somehow the box is not aligning to the others and the other box is not closing. The code is this

Build Release notes is this >>>>>

<tr>
                <td>
                <div class="Box1">
                <h2 class="QuickLinks">
                    Build Release Notes
                </h2>
                <div class="QuickLinks">

Supplemental Release notes is this

<td>
                 <td valign="top" class="auto-style1">      
                <div class="Box2">
                <h2 class="QuickLinks">
                    Supplemental Release Notes
                </h2>
                <div class="QuickLinks">

and the Case Assignment Training is this

 <div class="Box1">
                <h2 class="QuickLinks">
                    Case Assignment Enhancement Training
                </h2>
                   

I have placed the ending DIV tags to the Case Assignment Enhancement but it does not display it. suggestions?