When i am draggin data set from Repository i always get the same Error "

Hi @Hashmat_Sediqi123,

In data-science, you have to define a label (aka the target) : The variable you want to predict.
In your case, you have not defined a label, that's why your model is raising an error.
If you are a beginner in data-science and/or with RapidMiner, you can see the videos of the RapidMiner academy.
All the concepts are well explained in this academy : Please click on this link to access to the RapidMiner academy : 

https://academy.rapidminer.com/

Hope this helps,

Regards,

Lionel

@lionelderkrikor thanks for the reply , it work.