I am currently converting an ArcGIS 9.3.1 extension to 10. The extension has several toolbars, two of which have pulldown selection menus, which will have to be re-created using comboboxes. The pulldowns are both populated from an external database and contents can change through a session. As the combobox contents are dynamic I only want to populate them if and when the user wants to change the selection and I would like to do this each time the combobox receives focus. I'd intended to use the onfocus event to update the items in the combobox but I have tested the comboxes repeatedly and I can't see the onfocus event being fired. Has anyone else experienced this?