[totaltec]

Same template, I think you removed the product notifications and left the <tr></tr>
Original code:

  <tr>
        {if $active_modules.Product_Notifications ne '' and $config.Product_Notifications.prod_notif_enabled_P eq 'Y' and ($product.taxed_price ne 0 or $variant_price_no_empty)}
        <td>
          {include file="modules/Product_Notifications/product_notification_request_button.tpl" productid=$product.productid type="P"}
        </td>
        {/if}
  </tr>

I would search for <tr> in the template and look for one that has no <td>.

Look around line 100. I'm really just shooting in the dark though.