When I try to set a BindingSource.DataSource property using the Properties Window, I get an error saying "Object reference not set to an instance of an object". Here is a picture that shows the error...
I was playing around with DataGridViewBindingManager and ListConverter just before this happend.
Does anyone khow how to get rid of the error?
PS: If I create a new project, all is ok. This is only in my existing project.