Error in $NONPARAMETRIC

Dear all, When generating a VPC for a nonparametric ($NONPARAMETRIC subroutine on) model, I get the following error message from NONMEM 7.3.0 (installed on OSX 10.10.5, PsN 4.4.8), which doesn't occur with creating a VPC for a "normal" parametric model. > “ #TERE: > 0ERROR IN READING FILE : FILE15/16 USED BY DAT4 “ The control stream that causes this error is just a MAXEVAL=0 to filter the original data on IGNORE/ACCEPT and output needed variables defined in the model code, so it should not be a difficult task for NONMEM. Does anyone know what might be the cause of this error? Sincerely, Rob Het Radboudumc staat geregistreerd bij de Kamer van Koophandel in het handelsregister onder nummer 41055629. The Radboud university medical center is listed in the Commercial Register of the Chamber of Commerce under file number 41055629.