This is generally why I stay away from the data access threads, there are way too many variables. But since I had this exact same problem yesturday, I'll share my experience. Oh and by the way, I'm moving this thread to the VB.NET > Data Access category
.
First about the combobox: usually the combobox will be bound to two different datasources; one will fill the list (properties include DataSource, DisplayMember, ValueMember, ...) and the other is where you want the selected value stored (the property in this case would be under DataBindings, usually SelectedValue). Instead of using bindings to get the list of items, you could manually add the list using the Items property.
Your description of the data model you're using is lacking so I'll use the standard Orders-Products model. You also didn't mention binding to any property under the (DataBindings) property of the combo so all this based on many assumptions (another reason for me to stay away from the data access area)
.
In the example I'm giving, the form that the combobox is on would be a form for creating orders. The combobox would get the items for it's list from the Products table, but the information (the ProductID) is stored in the Orders table.
Using the Orders-Products model you would set the properties for the comboBox like this:
DataSource = ProductsTableBindingSource
DisplayMember = ProductName
ValueMember = ProductID
(DataBindings)
SelectedValue = OrdersBindingSource.ProductID
Now my problem was that I was using the Text property of the combobox to bind to the Orders table when I really should have been using the SelectedValue. The combobox was keeping the focus and the only way I could end the app was to press the Stop button in Visual Studio, even the close button on the form wasn't responding.
If this scenario doesn't fit your problem, please be more specific.
Good luck.