As of 1 September 2016, there is no limitation anymore to the validity of course results. All obtained results of courses remain valid until graduation.
Please note: partial results of a course (such as midterms/assignments) are only valid in the academic year in which they have been obtained.
This information can be read in the Teaching and Examination Regulations 2016-2017 (section 4, article 17).
www.eur.nl/ese/english/information_for/students/regulations/
In case of questions you can contact the study advisers.