I got this error when one of my properties that was required for the constructor was not public. Make sure all the parameters in the constructor go to properties that are public if this is the case:
using statements namespace someNamespace
public class ExampleClass {
//Properties - one is not visible to the class calling the constructor
public string Property1 { get; set; }
string Property2 { get; set; }
//Constructor
public ExampleClass(string property1, string property2)
{
this.Property1 = property1;
this.Property2 = property2; //this caused that error for me
}
}