RachelRachel 133k6767 Gold badges315315 silver badges510510 bronze badges 2 3 Rachel, you happen to be a wonderful genius!!! And that i am an fool. Thanks a lot for the solution. I was binding to self and didn't have a 'ConfigurationModel' property in my IncrementingTextBox class. So your DataContext for "video_length_textbox" https://pyramidsector71.blogspot.com