[Solved] ComboBox SelectedIndexChanged event is firing in Form Load event in C# and VB.Net

You will need to use the SelectionChangeCommitted  event and not the SelectedIndexChanged event.

The SelectionChangeCommitted event works similar to SelectedIndexChanged event, the only difference is that the SelectedIndexChanged event gets fired when the ComboBox selection is changed from code i.e. during DataBinding.

ComboBox SelectionChangeCommitted event