Thank for your reply, yes I had the workset in the model.
I figured out why it was not working, worksets in revit have ID’s [numbers] , and using the workset name as input will not work, you first need to extract that ID then use it as input.
Now I have another issue, its kind of nods efficiency, as you know worksets may contain more than one type of category, if you look at the snap shot below, you will see that, in my case, the workset “interiors” contain rooms, room separation lines and walls, but Element.SetParameter.ByName only accept one input, I need to find a way, to gather all these elements in one container node then link it to"elements" any thought on how to do that ?
Thanks
Moe