RachelRachel 133k6767 gold badges315315 silver badges510510 bronze badges 2 three Rachel, you're a lovely genius!!! And I am an idiot. Thank you so much for the answer. I was binding to self and did not have a 'ConfigurationModel' property in my IncrementingTextBox class. And the challenge the binding is owning https://m3mcommercialprojectsector57.blogspot.com