I have run into this silly mistake, and it took me 2 hours to figure it out
I am writing it down here for my own reference, and if you ever ran into this problem, hope that this can help you fix your problem quickly.
The problem is I had a datagrid column with the Header but not the Binding, for example
<data:DataGridTextColumn Header=”MyProperty” />
This will cause the below error at runtime

To fix it, all I had to do is to put the Binding in it
<data:DataGridTextColumn Header=”MyProperty” Binding={Binding MyProperty} />
Hope this helps
![Reblog this post [with Zemanta]](http://img.zemanta.com/reblog_e.png?x-id=acf386e2-110e-4d7d-bb6c-3b035a15b8aa)



