treenode.appendChild(newNode) thows error insertBefore is null
I am running extjs 4.0.7 in IE8 and IE9. I currently am creating a TreeGrid by dynamically adding child nodes to other nodes using the appendChild() method. This seems to work fine most of the time. However, when browsing to the page through an outlook plugin it throws an error insertBefore is null or undefined. The outlook plugin is part of Microsoft Dynamic CRM 2011 and allows browsing CRM pages without needed to go through a separate IE window.
I appreciate any suggestions on how to fix this issue.