Thanks for writing and for your question.
Q3 2009 release of RadControls for WinForms introduced some improvements in databinding mechanism of RadComboBox. Currently, the Items
collection is populated after the Binding Context
has been initialized (which does not happen in the constructor).
In your case, my suggestion is that you access the combo box items in the OnLoad
event of your form or in the BindingContextChanged
event of RadComboBox
I hope this is helpful. You can write back anytime you need further assistance.
the Telerik team