In a winform application running on windows 7 I want the change the background color of a combobox to highlight it.
The comboxbox has a DropDownStyle of DropDownList.
Since you lose the 3D effects anyway with Igby Largeman's solution you're better off changing the FlatStyle property to Flat. The background color seems to be obeyed even in Windows 7 that way, and without re-implementing any low-level events.
I would consider this a bug on Microsoft's part...