paint blendshape weight tool and set driven key....crash


i have this problem :
1-i have a head with some blendshapes
2-i Paint some weights on them, with the paint blendshape weight tool.
3- when i select a blendhape in the shape editor, and right select /set driven key…maya slow down and nothing append…cant clic anywere.
if my model have only one blendshape, the set driven key window open with this error in the mel :
[b]error: Attribute name not recognized

[/b]could you help me ?

thank you


i tryed it on many heads and with maya 2015 and 2017