Cannot save model 'dfig' in the MDL file format because some of characters it contains are not valid in the current character encoding, 'US-ASCII'. Either remove these charac

how to remove this problem ,i want to create the same model in old version of matlab 2010a ,and i had the same model on 2016a when i export it i get the erroe box ((Cannot save model 'dfig' in the MDL file format because some of characters it contains are not valid in the current character encoding, 'US-ASCII'. Either remove these characters from the model, or save the model in the SLX file format by using a file name with extension '.slx'.))