Are you working in C# 2.0? If so, its recommended to use generic Lists in rather than the non-generic ArrayList.
The following code should help:
Note that you are not updating the data here!
The Developing Developer
List<string> items = new List<string>();
// populate list
// to remove...
// Get listIndex from DropDown and remove the Item.
int idx = comboBox1.SelectedIndex;
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