NONMEM Error on SAEM but not FOCEI

Hello NMusers, I have created a model that fit ok with FOCE+I. When I try to fit with SAEM, I get the following error: """ ERROR IN TRANS4 ROUTINE: Q IS ZERO Elapsed estimation time in seconds: 0.00 INDIVIDUAL OBJECTIVE FUNCTION VALUES ARE ALL ZERO. PROBLEM ENDED """ The data is very small, but the model seems acceptable from bootstrap on FOCE+I. Any ideas are appreciated! Thank you, Omar Omar Elashkar, B.Pharm, MSc Graduate Assistant University of Florida | College of Pharmacy