ADODB forces all the fields in a query result object to be upper-case with the Oracle driver. During the setup_enrolments() method, the database enrolment plug-in is specifically looking for a field name ("enrolremotecoursefield") using lower-case when synchronizing user enrolments during login. This is perhaps a problem with the Oracle ADODB driver but as a fix for the enrolment plug-in, I have a patch here that works which looks for the field name in either lower or upper-case.