If the database is updated then you can rebind the DownDropDownTree in the OnTaskUpdate
event. However if both controls are in different RadAjaxPanels
then the observed behavior is expected. They must be in the same RadAjaxPanel or you will have to use RadAjaxManager, so when task is updated the dropdowntree should be updated too. Please try to disable the ajax to see if it will be working correctly.
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