Parse Nominal ERROR

Hello!

I am trying to parse a nominal attribute to numerical, but it seems like there is some format issue. When I use "Nominal to Numerical" Operator, I get one new column for each value of the attribute i am trying to parse.

If I use "Parse Numbers" Operator, It shows me the error "The setup does not seem to contain any obvious errors, but you should check the log messages or activate the debug mode in the settings dialog in order to get more information about this problem"

Any ideas?

Thanks in advance.