My solution was for a winTree with columns in outlook mode.  In that mode the winTree works a bit like a grid and a bit like a tree.

If you are using standard mode, then I'm guessing you have no columns and you are looking to have a selection checkbox on the node itself?

There is a property called CheckedState on the node.  Never used it, but maybe you can find somethign useful on it in the onlien documentation or just experiment with it a bit...

 thanks, I guess your solution was for a grid.

I found the way, I wanted standard and to show checkbox. it was setting the Override->NodeStyle

Do you know how I can iterate the checkbox and check them? Can I disable the checkbox also?