I am a beginner of RapidMiner.
I'd like to test with my data... but it always report me a error message like as attached file.
Please help me to solve this problem.
The first message is not a big problem. Just a hint that you're referring to your data using an absolute path, which means your process is not as portable as it could be.
To get rid of the second message, use the Set Role operator for assigning the "label" role to your target variable.