On Wed, Mar 13, 2013 at 9:06 PM, Mark Jas <mark(a)nieuwenborg.nl> wrote: Could be. TRANSPORT_ERROR normally happens when a request made by the tree fails (usually because the URL is bad). The tree uses the REST system to fetch its data, so all requests made by the tree are /rest/ requests. It would be of great help if you could tell us what requests are failing (their URL is important). In order to check this you can use Firefox with its Firebug extension. This extension has a Console tab where you can see all the (AJAX) requests made by the editor and its tree, if the console was opened before the page was loaded, otherwise you need to reload the page. The failed requests are displayed in red so they are easy to notice. You can click on each request to get more information, but more importantly you can right click to get the full URL with parameters. Post here the bad URLs and also the URL for the edit mode. The things to check are: * are the REST URLs using the same scheme (HTTP/HTTPS) as the edit mode URL? * do they have the same domain? * is the REST system working when Kerberos SSO is enabled? Thanks, Marius