Everything works fine except for the undo button on the toolstrip. When I edit something on the grid and click undo, the value on the grid does not change, however the business object is correct.

I took a look at your new sample program in 1.6 'BusinessBindingSourceExample' and the undo seems to work fine in this example. I looked at the click event and discovered that all you are doing is using 'Undo()', which I assume is what is happening behind the scenes when you click on the undo button on the toolstrip.

As a test, I added a button on my form and executed 'Undo()' in the click event.  This worked fine, so my question is why is the undo button on the toolstrip not working properly? 

Thanks

Tim