Michael,

You're getting this error because the business object project is not compiling properly, which can be fixed by my comment below.

>C:\MM.net\Windows Projects\Order System CSharp\SecuritySetupForm.cs(8): The type or namespace name 'Business' does not exist in the class or namespace 'Acme.OrderSystem' (are you missing an assembly reference?)

>C:\MM.net\Business Objects\Order System Business Objects CSharp\Order System Business Objects CSharp\OrderDetailDataAccessSql.cs(95): 'Acme.OrderSystem.Business.OrderDetailDataAccessSql.CreateDataAccessObject(string)': no suitable method found to override

As indicated by Jason, you've got this method override code in the wrong place. You should put it in the OrderDetail business object rather than the data access class. Recheck "Step 5: Creating an Order Detail Business Object" and note the instructions in step 16:

16. In this last step, you override the business object's CreateDataAccessObject method so it instantiates your custom data access class. To do this, go to the Solution Explorer, right-click on the OrderDetail business object and select View Code from the shortcut menu. 

Regards,