Well, I run traincascade by "accident " , I mean that some parameters weren't good. So i stoped it by killing the proces and now it refuse to start again with new parameters, I've got this message when i try to do so :
"Training parameters are loaded from the parameter file in data folder! Please empty the data folder if you want to use your own set of parameters."
And the thing is , I don't find the data folder to empty it, maybe hidden some where ?