Help with a parallel process

Hi R-Core,

i am using nnet and DEoptim,

Xcc=matrix(rnorm(100,0.5,0.08),50,2)
Ycr=matrix(rnorm(50,0.2,0.05),50,1)


pred_regm1 <- function(A) {
   A1=A[1]
   A2=A[2]
   A3=A[3]
   regm1 <-
nnet(Xcc,Ycr,entropy=T,size=A1,decay=A2,maxit=2000,trace=F,Hess=T,rang=A3,skip=T)
   dif=sum((predict(regm1,Xcc)-Ycr)^2)
   return(dif)
}

somar=DEoptim(pred_regm1,c(1,0.00001,0.01), c(25,0.999,0.95),
               control = DEoptim.control(steptol=25,trace =
FALSE,itermax=500,parallelType=1))


but implemented parallel process, i have next error:

Error en checkForRemoteErrors(val) :   4 nodes produced errors; first
error: could not find function "nnet"

how I can solve my mistake?

Thanks and kind regards