>>This does not make sense - looks like a bug. Are you adding this combobox in run-time? What is the design time visible property set to?
>
>Nor does it make sense to me. ComboBox is added at design-time, not at run-time. Visible property is true. I didn't notice anything queer in the debugger, with other relevant properties including Top, .Left, .BackColor.

There was some relevant thread a couple of months back by Gary W.

Update. This thread doesn't seem to close to your problem, but anyway Strange Error on .AddProperty Thread #1384470 Message #1384470