[R] error in random forest

[Nagu]

Hi,

I get the following error when I try to predict the probabilities of a
test sample:

Error in predict.randomForest(fit.EBA.OM.rf.50, x.OM, type = "prob") :
  New factor levels not present in the training data

I have about 630 predictor variables in the dataset x.OM (25 factor
variables and the remaining are continuous variables). Any ideas on
how to trace it?

Thank you,
Nagu