Yep, tried that. I think this is a memory issue as it works on a *clean* form on my PC but not within the application. Although the navigation menu for the system is also a treeview. The PC I use here dies at least once a day so I know there are problems with it.

Thanks anyway,

>
>I notice you haven't gotten any answers on this (and this is a second posting?). Have you figured anyhting out?
>
>Just a simple idea, have you tried toggleing the _vfp.AutoYield property?