I'm creating a datamining process with weka so I have added an

-ArffLoader

selecting the datasource file, linked to a

-ClassAssigner

before pass the input to a classifier I need to use some filters, so I have linked the ClassAssigner out to a filter series, now the problem is that seems I cannot link the filter out to the classifier, when I click with right click of the mouse on dataset when I'm on NominalToString filter to attach its outo to BayesNet classifier, Weka show the arrow but this doesn't link to classifier. I have tried with different filter series, always the same problem.

What is wrong in the shown section of my workflow?